Apollo Guidance Computer - Knowledge (XXG)

589: 1411:. The memory cycle took 12 timing pulses (11.72 μs). The cycle began at timing pulse 1 (TP1) when the AGC loaded the memory address to be fetched into the S register. The memory hardware retrieved the data word from memory at the address specified by the S register. Words from erasable memory were deposited into the G register by timing pulse 6 (TP6); words from fixed memory were available by timing pulse 7. The retrieved memory word was then available in the G register for AGC access during timing pulses 7 through 10. After timing pulse 10, the data in the G register was written back to memory. 1800:. The address spaces were extended by employing the Bank (fixed) and Ebank (erasable) registers, so the only memory of either type that could be addressed at any given time was the current bank, plus the small amount of fixed-fixed memory and the erasable memory. In addition, the bank register could address a maximum of 32 kilowords, so an Sbank (super-bank) register was required to access the last 4 kilowords. All across-bank subroutine calls had to be initiated from fixed-fixed memory through special functions to restore the original bank during the return: essentially a system of 820: 1575: 1844: 1652:(matrix × vector) instruction, could be mixed with native AGC code. While the execution time of the pseudo-instructions was increased (due to the need to interpret these instructions at runtime) the interpreter provided many more instructions than AGC natively supported and the memory requirements were much lower than in the case of adding these instructions to the AGC native language which would require additional memory built into the computer (in 597: 3975: 3851: 832: 361: 1705:. The first command module flight was controlled by a software package called CORONA whose development was led by Alex Kosmala. Software for lunar missions consisted of COLOSSUS for the command module, whose development was led by Frederic Martin, and LUMINARY on the lunar module led by George Cherry. Details of these programs were implemented by a team under the direction of 1945: 840: 417: 409: 1377: 401: 38: 353: 3255: 3251: 1929:

excited by a different source of 800 Hz AC than the one used by the computer as a timing reference. The two 800 Hz sources were frequency locked but not phase locked, and the small random phase variations made it appear as though the antenna was rapidly "dithering" in position, even though

1238:

in such a way as to propagate a carry for multi-precision add/subtract. If the result has no overflow (leftmost 2 bits of A the same), nothing special happens; if there is overflow (those 2 bits differ), the leftmost one goes the memory as the sign bit, register A is changed to +1 or −1 accordingly,

1388:

Block I AGC memory was organized into 1 kiloword banks. The lowest bank (bank 0) was erasable memory (RAM). All banks above bank 0 were fixed memory (ROM). Each AGC instruction had a 12-bit address field. The lower bits (1-10) addressed the memory inside each bank. Bits 11 and 12 selected the bank:

1924:

The problem was not a programming error in the AGC, nor was it pilot error. It was a peripheral hardware design bug that had already been known and documented by Apollo 5 engineers. However, because the problem had only occurred once during testing, they concluded that it was safer to fly with the

1628:

called the 'Waitlist' which scheduled timer-driven 'tasks', controlled the computer. Tasks were short threads of execution which could reschedule themselves for re-execution on the Waitlist, or could kick off a longer operation by starting a 'job' with the Exec. Calculations were carried out using

1526:

The AGC had a 16-bit read bus and a 16-bit write bus. Data from central registers (A, Q, Z, or LP), or other internal registers could be gated onto the read bus with a control signal. The read bus connected to the write bus through a non-inverting buffer, so any data appearing on the read bus also

1513:

In the standby mode, the AGC slept most of the time; therefore it was not awake to perform the Pinc instruction needed to update the AGC's real time clock at 10 ms intervals. To compensate, one of the functions performed by the AGC each time it awoke in the standby mode was to update the real

1323:

were treated as fractions (notional decimal point just to right of the sign bit), so you could produce garbage if the divisor was not larger than the dividend; there was no protection against that situation. In the Block II AGC, a double-precision dividend started in A and L (the Block II LP), and

1767:

The decision to expand the memory and instruction set for Block II, but to retain the Block I's restrictive three-bit op. code and 12-bit address had interesting design consequences. Various tricks were employed to squeeze in additional instructions, such as having special memory addresses which,

1530:

Data transfers worked like this: To move the address of the next instruction from the B register to the S register, an RB (read B) control signal was issued; this caused the address to move from register B to the read bus, and then to the write bus. A WS (write S) control signal moved the address

1509:

switch. This mode turned off the AGC power, except for the 2.048 MHz clock and the scaler. The F17 signal from the scaler turned the AGC power and the AGC back on at 1.28 second intervals. In this mode, the AGC performed essential functions, checked the standby allowed switch, and, if still

1418:

The lower 15 bits of each memory word held AGC instructions or data, with each word being protected by a 16th odd parity bit. This bit was set to 1 or 0 by a parity generator circuit so a count of the 1s in each memory word would always produce an odd number. A parity checking circuit tested the

1884:

During this part of the approach, the processor would normally be almost 85% loaded. The extra 6,400 cycle steals per second added the equivalent of 13% load, leaving just enough time for all scheduled tasks to run to completion. Five minutes into the descent, Buzz Aldrin gave the computer the

1207:

Exchange the contents of memory with the contents of the A register. If the specified memory address is in fixed (read-only) memory, the memory contents are not affected, and this instruction simply loads register A. If it is in erasable memory, overflow "correction" is achieved by storing the

1751:

A Block II version of the AGC was designed in 1966. It retained the basic Block I architecture, but increased erasable memory from 1 to 2 kilowords. Fixed memory was expanded from 24 to 36 kilowords. Instructions were expanded from 11 to 34 and I/O channels were implemented to replace the I/O

1414:

The AGC memory cycle occurred continuously during AGC operation. Instructions needing memory data had to access it during timing pulses 7–10. If the AGC changed the memory word in the G register, the changed word was written back to memory after timing pulse 10. In this way, data words cycled

1496:

Interrupts could be triggered when the counters overflowed. The T3rupt and Dsrupt interrupts were produced when their counters, driven by a 100 Hz hardware clock, overflowed after executing many Pinc subsequences. The Uprupt interrupt was triggered after its counter, executing the Shinc

1973:

In 2003, Ron Burkey initiated the Virtual AGC Project, aiming to recover the Apollo Guidance Computer (AGC) source code and build a functional emulator. As part of this project, the original code, transcribed and digitized from 1960s hard copies, was made available through the

810:

because whatever was stored there would emerge shifted or rotated by one bit position, except for one that shifted right seven bit positions, to extract one of the seven-bit interpretive op. codes that were packed two to a word. This was common to Block I and Block II AGCs.

1667:

A set of interrupt-driven user interface routines called 'Pinball' provided keyboard and display services for the jobs and tasks running on the AGC. A set of user-accessible routines were provided to let the astronauts display the contents of various memory locations in

3293:- Manual for CSM and LEM AGC software used on the Apollo 15 mission, including detailed user interface procedures, explanation of many underlying algorithms and limited hardware information. Note that this document has over 500 pages and is over 150 megabytes in size. 1700:

decision capability. When the design requirements for the AGC were defined, necessary software and programming techniques did not exist so they had to be designed from scratch. Many of the trajectory and guidance algorithms used were based on earlier work by

729:, first by five using a ring counter to produce a 102.4 kHz signal. This was then divided by two through 17 successive stages called F1 (51.2 kHz) through F17 (0.78125 Hz). The F10 stage (100 Hz) was fed back into the AGC to increment the 3243: 3237: 1093:

means "decremented but not below zero". Therefore, when the AGC performs the DABS function, positive numbers will head toward plus zero, and so will negative numbers but first revealing their negativity via the four-way skip below. The final step in

1089:(DABS) of the data was then computed and stored in the A register. If the number was greater than zero, the DABS decrements the value by 1; if the number was negative, it is complemented before the decrement is applied—this is the absolute value. 1960:

to demonstrate the practicality of computer driven FBW. The AGC used in the first phase of the program was replaced with another machine in the second phase, and research done on the program led to the development of fly-by-wire systems for the

1517:

The standby mode was designed to reduce power by 5 to 10 W (from 70 W) during midcourse flight when the AGC was not needed. However, in practice, the AGC was left on during all phases of the mission and this feature was never used.

304:

Astronauts communicated with the AGC using a numeric display and keyboard called the DSKY (for "display and keyboard", pronounced "DIS-kee"). The AGC and its DSKY user interface were developed in the early 1960s for the Apollo program by the

1182:. This method is used to implement arrays and table look-ups; since the addition was done on both whole words, it was also used to modify the op. code in a following (extracode) instruction, and on rare occasions both functions at once. 1161:

when the value being tested was known to be never positive, which occurred more often than one might suppose. That left two whole words unoccupied, and a special committee was responsible for assigning data constants to these

1672:

or decimal in groups of 1, 2, or 3 registers at a time. 'Monitor' routines were provided so the operator could initiate a task to periodically redisplay the contents of certain memory locations. Jobs could be initiated.

1819:, the programmer who requested it). This instruction does not generate an interrupt, rather it performs two actions that are common to interrupt processing. The first action, inhibits further interrupts (and requires a 1709:. Hamilton was very interested in how the astronauts would interact with the software and predicted the types of errors that could occur due to human error. In total, software development on the project comprised 1400 1288:. The fact that overflow is a state rather than an event forgives limited extents of overflow when adding more than two numbers, as long as none of the intermediate totals exceed twice the capacity of a word. 1309:

Multiply the contents of register A by the data at the referenced memory address and store the high-order product in register A and the low-order product in register LP. The parts of the product agree in

1827:

register is loaded with the current value of the program counter (Z). It was only used once in the Apollo software, for setting up the DAP cycle termination sequence in the Digital Autopilot of the

341:

which did not need a lunar module for its lunar orbit mission. The AGC in the command module was the center of its guidance, navigation and control (GNC) system. The AGC in the lunar module ran its

1319:

Divide the contents of register A by the data at the referenced memory address. Store the quotient in register A and the absolute value of the remainder in register Q. Unlike modern machines,

1368:. The control pulses were the signals which did the actual work of the instruction, such as reading the contents of a register onto the bus, or writing data from the bus into a register. 1925:

existing hardware that they had already tested, than to fly with a newer but largely untested radar system. In the actual hardware, the position of the rendezvous radar was encoded with

1481:. These were memory locations which functioned as up/down counters, or shift registers. The counters would increment, decrement, or shift in response to internal inputs. The increment ( 404:

Photograph of the dual NOR gate chip used to build the Block II Apollo Guidance Computer. Connections (clockwise from top center) ground, inputs (3), output, power, output, inputs (3).

1404:

The Block I AGC initially had 12 kilowords of fixed memory, but this was later increased to 24 kilowords. Block II had 36 kilowords of fixed memory and 2 kilowords of erasable memory.

468:

According to Kurinec et al, the chips were welded onto the boards rather than soldered as might be expected. Apollo Guidance Computer logic module drawings specify resistance-welding.

1936:'s software and computer design saved the Apollo 11 landing mission. Had it not been for Laning's design, the landing would have been aborted for lack of a stable guidance computer. 495:, the later Block II version (used in the crewed flights) used about 2,800 ICs, mostly dual three-input NOR gates and smaller numbers of expanders and sense amplifiers. The ICs, from 391:) of the lunar module, to be used in the event of failure of the LM PGNCS. The AGS could be used to take off from the Moon, and to rendezvous with the command module, but not to land. 356:

The display and keyboard (DSKY) interface of the Apollo Guidance Computer mounted on the control panel of the command module, with the flight director attitude indicator (FDAI) above

5037: 1644:

with more complex and capable pseudo-instructions than the native AGC. These instructions simplified the navigational programs. Interpreted code, which featured double precision

2090: 1474:

The AGC responded to each interrupt by temporarily suspending the current program, executing a short interrupt service routine, and then resuming the interrupted program.

1653: 1597:. The bulk of the software was on read-only rope memory and thus could not be changed in operation, but some key parts of the software were stored in standard read-write 3411: 3374: 4009: 1714: 1345:. Simple instructions, such as TC, executed in a single subsequence of 12 pulses. More complex instructions required several subsequences. The multiply instruction ( 5950: 5960: 5148: 4331: 4850: 3689: 2011: 3068: 251:(LM). The AGC provided computation and electronic interfaces for guidance, navigation, and control of the spacecraft. The AGC was the first computer based on 3885: 1073:

A complex conditional branch instruction. The A register was loaded with data retrieved from the address specified by the instruction. (Because the AGC uses

5007: 4573: 4390: 5970: 2038:(calculate and display DELTAH, once) would have only added approximately 5% load to the system, and would have only done so once, when ENTER was pressed. 3231: 1889:, which instructed it to periodically calculate and display DELTAH (the difference between altitude sensed by the radar and the computed altitude). The 2354: 1982:. This effort gained renewed attention in mid-2016 when former NASA intern Chris Garry uploaded the code to GitHub, generating significant media buzz. 1965:. The AGC also led, albeit indirectly, to the development of fly-by-wire systems for the generation of fighters that were being developed at the time. 1881:

from the rendezvous radar (tracking the orbiting command module), intentionally left on standby during the descent in case it was needed for an abort.

1284:

Add the contents of memory to register A and store the result in A. The 2 leftmost bits of A may be different (overflow state) before and/or after the

685:

The command module has two DSKYs connected to its AGC: one located on the main instrument panel and a second located in the lower equipment bay near a

4353: 1138:. The absolute value function was deemed important enough to be built into this instruction; when used for only this purpose, the sequence after the 5002: 3694: 3669: 3007: 1877:("Executive overflow - NO VAC AREAS"). The response of the AGC to either alarm was a soft restart. The cause was a rapid, steady stream of spurious 588: 1389:

00 selected the erasable memory bank; 01 selected the lowest bank (bank 1) of fixed memory; 10 selected the next one (bank 2); and 11 selected the

5074: 716:

which the AGC used to perform internal operations. The 1.024 MHz clock was also divided by two to produce a 512 kHz signal called the

4827: 733:

and other involuntary counters using Pinc (discussed below). The F17 stage was used to intermittently run the AGC when it was operating in the

3404: 3158: 2740: 2371: 1625: 1578: 876:(super-bank): 1-bit extension to Fbank, required because the last 4 kilowords of the 36-kiloword ROM was not reachable using Fbank alone 5771: 4895: 4158: 4002: 3741: 3684: 3679: 3319: 1909:

up". The AGC software had been designed with priority scheduling, and automatically recovered, deleting lower priority tasks including the

1060:

An unconditional branch to the address specified by the instruction. The return address was automatically stored in the Q register, so the

1633:, but display readouts were in units of feet, feet per second, and nautical miles – units that the Apollo astronauts were accustomed to. 5955: 5781: 4922: 3657: 3199: 2463: 2457: 2259: 2193: 936:: General-purpose buffer register, also used to pre-fetch the next instruction. At the start of the next instruction, the upper bits of 454: 4049: 3711: 2769: 2593: 518:

The use of a single type of IC (the dual NOR3) throughout the AGC avoided problems that plagued another early IC computer design, the

481: 325:, but computers flew most of Project Apollo except briefly during lunar landings. Each Moon flight carried two AGCs, one each in the 5089: 4917: 4890: 4269: 3664: 2688: 2098: 4240: 1731:

The Apollo Guidance computer has been called "The fourth astronaut" for its role in helping the three astronauts who relied on it:

1419:

parity bit during each memory cycle; if the bit didn't match the expected value, the memory word was assumed to be corrupted and a

2235: 189:

DSKY, IMU, Hand Controller, Rendezvous Radar (CM), Landing Radar (LM), Telemetry Receiver, Engine Command, Reaction Control System

5945: 5904: 5467: 4360: 4326: 4321: 4205: 3878: 3854: 3397: 3019: 2387: 1333:

Subtract (ones' complement) the data at the referenced memory address from the contents of register A and store the result in A.

1267:

to fixed memory) to complete the formation of the carry (+1, 0, or −1) into the next higher-precision word. Angles were kept in

5965: 5879: 5776: 5177: 5084: 4885: 4128: 4106: 3995: 3957: 3482: 373: 51: 3107: 2284: 364:

Partial list of numeric codes for verbs and nouns in the Apollo Guidance Computer, printed for quick reference on a side panel

4624: 4059: 3772: 3652: 3622: 3179: 2327: 1677: 1637: 1324:

the correctly signed remainder was delivered in L. That considerably simplified the subroutine for double precision division.

434: 306: 3260: 1534:

Several registers could be read onto the read bus simultaneously. When this occurred, data from each register was inclusive-

500: 134: 2146: 1752:

registers on Block I. The Block II version is the one that actually flew to the moon. Block I was used during the uncrewed

1397:

memory, because they were always available, regardless of the contents of the Bank register. Banks 3 and above were called

5079: 4927: 4761: 4375: 4336: 4193: 3762: 3731: 3706: 3263:– An AGC system programmer discusses some obscure details of the development of AGC, including specifics of Ed's Interrupt 2392: 1706: 679: 675: 2353:

Butrica, Andrew J. (2015). "Chapter 3: NASA's Role in the Manufacture of Integrated Circuits". In Dick, Steven J. (ed.).

2313: 5516: 5361: 5356: 5278: 4754: 4715: 4370: 4365: 4299: 4111: 3906: 3831: 3551: 2328:"Apollo Requirements for Process Control and Fabrication of Resistance-Welded Electronic Circuit Modules and Assemblies" 278: 4235: 3296: 1198:

25). This is the instruction used to return from interrupts. It causes execution to resume at the interrupted location.

5940: 5143: 4840: 4538: 3978: 3871: 3810: 3642: 3094: 2992: 2790: 2730: 1740: 3962: 3268:

Documentation of AGC hardware design, and particularly the use of the new integrated circuits in place of transistors

526: 484:(IMP) in 1963, IC technology was later adopted for the AGC. The Apollo flight computer was the first computer to use 5793: 5440: 4857: 4348: 4316: 4086: 4074: 4054: 3777: 3721: 3328:– Ronald Burkey's AGC simulator, plus source and binary code recovery for the Colossus (CSM) and Luminary (LEM) SW. 1609: 785: 694: 644: 556:. Both had cycle times of 11.72 microseconds. The memory word length was 16 bits: 15 bits of data and one odd- 3318:– John Pultorak's successful project to build a hardware replica of the Block I AGC in his basement. Mirror site: 5975: 5884: 5847: 5837: 4225: 3726: 3674: 3586: 2579: 1656:

memory was very expensive). The average pseudo-instruction required about 24 ms to execute. The assembler, named

1905:

alarm occurred. When reporting the second alarm, Aldrin added the comment "It appears to come up when we have a

1122:. The primary purpose of the count was to allow an ordinary loop, controlled by a positive counter, to end in a 5899: 5242: 5219: 5069: 5031: 4867: 4817: 4812: 4289: 4183: 4091: 3916: 3757: 3716: 3591: 3556: 3477: 3225: 3213: 2006: 1617: 4096: 1098:

is a four-way skip, depending upon the data in register A before the DABS. If register A was greater than 0,

5852: 5635: 5529: 5493: 5410: 5394: 5236: 5025: 4984: 4972: 4835: 4749: 4670: 4435: 4039: 3699: 3612: 3509: 2505: 2397: 824: 761: 561: 496: 3119: 1689: 5658: 5630: 5540: 5505: 5254: 5248: 5230: 4964: 4958: 4862: 4766: 4657: 4596: 4458: 4101: 3576: 2131: 1320: 1208:

leftmost of the 16 bits in A as the sign bit in memory, but there is no exceptional behavior like that of

870:: 3-bit RAM bank register, to select the 256-word RAM bank when addressing in the erasable-switchable mode 504: 420: 3069:"The code that took America to the moon was just published to GitHub, and it's like a 1960s time capsule" 1693: 5832: 5741: 5487: 5199: 5017: 4776: 4744: 4702: 4614: 4415: 4230: 4220: 4210: 4200: 4170: 4153: 4018: 3517: 3503: 2169: 2114: 2001: 1341:. The timing pulses were named TP1 through TP12. Each set of 12 timing pulses was called an instruction 647: 446: 384: 326: 244: 3278: 2940:"NASA SP-2000-4224 — Computers Take Flight: A History of NASA's Pioneering Digital Fly-By-Wire Project" 2455:

Peirce, C. S. (manuscript winter of 1880–81), "A Boolian Algebra with One Constant", published 1933 in

1832: 819: 2893: 2815: 5862: 5798: 5384: 5106: 4996: 4943: 4475: 4188: 4044: 4026: 3826: 3736: 3647: 2939: 1685: 1681: 1598: 1493:) was handled by one subsequence of microinstructions inserted between any two regular instructions. 546: 438: 164: 160: 5909: 5511: 1527:

appeared on the write bus. Other control signals could copy write bus data back into the registers.

1251:

to the no-overflow logic; when it is a normal possibility (as in multi-precision add/subtract), the

697:(FDAI), controlled by the AGC, was located above the DSKY on the commander's console and on the LM. 5894: 5714: 5565: 5547: 5499: 5153: 5100: 4905: 4900: 4877: 4793: 4675: 4530: 4425: 4284: 3798: 3767: 3522: 3498: 1574: 1555: 1235: 1074: 919: 899: 577: 569: 330: 248: 1930:

it was completely stationary. These phantom movements generated the rapid series of cycle steals.

221:

24 in × 12.5 in × 6.5 in (61 cm × 32 cm × 17 cm)

5766: 5758: 5610: 5585: 5389: 5264: 4788: 4729: 4609: 4341: 4069: 3528: 3187: 1933: 1852: 1613: 1221:

Load register A with the ones' complement of the data referenced by the specified memory address.

746: 706: 477: 450: 426: 255: 130: 2912: 2468: 2649: 2058: 1816: 1077:

notation, there are two representations of zero. When all bits are set to zero, this is called

5719: 5686: 5602: 5534: 5435: 5425: 5415: 5346: 5341: 5336: 5259: 5188: 5094: 5054: 4687: 4637: 4587: 4563: 4445: 4385: 4380: 4262: 4178: 3154: 2765: 2736: 2715: 2367: 2094: 1697: 1590: 1478: 690: 667: 663: 5889: 5822: 5663: 5570: 5524: 5331: 5326: 5321: 5316: 5311: 5301: 5171: 5138: 5049: 5044: 4953: 4805: 4800: 4783: 4771: 4710: 4274: 4252: 4138: 4116: 4034: 3804: 3596: 3581: 3219: 3148: 2034:(in this case, 68, DELTAH) approximately twice per second. Had Aldrin known this, a simple 1843: 1381: 1272: 1268: 1170:

Add the data retrieved at the address specified by the instruction to the next instruction.

553: 550: 519: 290: 286: 236: 175: 171: 1407:

The AGC transferred data to and from memory through the G register in a process called the

5803: 5788: 5736: 5640: 5615: 5452: 5445: 5296: 5291: 5286: 5225: 5133: 5123: 4845: 4680: 4632: 4395: 4279: 4247: 4148: 4143: 4064: 3942: 3921: 3207: 3095:"Original Apollo 11 Guidance Computer (AGC) source code for the command and lunar modules" 2547: 1641: 1461: 980: 771: 730: 3305:

Original Apollo 11 Guidance Computer (AGC) source code for the command and lunar modules.

3184:– The infamous memo that served as de facto official documentation of the instruction set 2692: 17: 5914: 5748: 5731: 5724: 5620: 5477: 5214: 5128: 5059: 4642: 4604: 4553: 4548: 4543: 4257: 4081: 3472: 3467: 3420: 1913:

display task, to complete its critical guidance and control tasks. Guidance controller

1878: 1732: 1702: 1582: 847:

The AGC had additional registers that were used internally in the course of operation:

654:, limiting the update rate. Three five-digit signed numbers could also be displayed in 605: 458: 318: 240: 2217: 596: 5934: 5709: 5625: 4665: 4647: 4440: 4133: 3434: 3273: 2617: 2484: 2082: 1962: 1725: 1630: 725: 442: 322: 294: 271: 259: 1601:

and could be overwritten by the astronauts using the DSKY interface, as was done on

5919: 5857: 5673: 5650: 5462: 5183: 4121: 3793: 3571: 2840: 1991: 1957: 1862: 1828: 1792:). Other instructions were implemented by preceding them with a special version of 1710: 1645: 1175: 713: 342: 3299:

for Command Module code (Comanche054) and Lunar Module code (Luminary099) as text.

2865: 2429: 1393:

831: 360: 345:(primary guidance, navigation and control system), with the acronym pronounced as 3290: 5704: 5668: 5379: 5351: 5209: 5064: 3837: 2887: 2885: 2285:"Recreating History: Making the Chip that went on the Moon in 1969 on Apollo 11" 2154: 1953: 1918: 1914: 1848: 1801: 1736: 1594: 1581:

standing next to listings of the software she and her MIT team produced for the

1510:

enabled, turned off the power and went back to sleep until the next F17 signal.

1035:, were directly accessed by the 3-bit op. code. The final three were denoted as 640:

specified which data were affected by the action specified by the Verb command.

530: 298: 2757: 2631: 2431:

MIT's Role in Project Apollo: Final report on contracts NAS 9-163 and NAS 94065

1713:

of effort, with a peak workforce of 350 people. In 2016, Hamilton received the

537:

from which any other gate can be made, though at the cost of using more gates.

491:

While the Block I version used 4,100 ICs, each containing a single three-input

5590: 5580: 5575: 5557: 5457: 5430: 4692: 4525: 4495: 4215: 3926: 3617: 3380: 3356: 3343: 1979: 1893:

added another 10% to the processor workload, causing executive overflow and a

1131: 709: 621: 557: 534: 282: 1470:

was generated each time a 16-bit word of uplink data was loaded into the AGC.

1460:

was generated at regular intervals from a hardware timer to update the AGC's

888:: 16-bit memory buffer register, to hold data words moving to and from memory 643:

Each digit was displayed via a green (specified as 530 nm) high-voltage

461:, Ramon Alonso, and Hugh Blair-Smith. The flight hardware was fabricated by 5681: 5678: 5420: 4490: 4468: 3444: 3340:

Shareware Lunar Lander Simulator with a working AGC and DSKY (Windows only).

3302: 3102: 2707: 1866: 1621: 1602: 1432: 508: 3325: 3002: 1554:

through the bus and could complement (invert) data through the C register,

3389: 2673: 2283:

Kurinec, Santosh K; Indovina, Mark; McNulty, Karl; Seitz, Matthew (2021).

1415:

continuously from memory to the G register and then back again to memory.

806:

There were also four locations in core memory, at addresses 20–23, dubbed

720:; this signal was used to synchronize external Apollo spacecraft systems. 624:-style keyboard. Commands were entered numerically, as two-digit numbers: 5696: 4568: 4515: 3987: 3449: 3439: 3368: 2132:"How did the Apollo flight computers get men to the moon and back ?" 1948:

Fly By Wire testbed aircraft. The AGC DSKY is visible in the avionics bay

1761: 1757: 1753: 1562:. This was accomplished by inverting both operands, performing a logical 861: 854:: 12-bit memory address register, the lower portion of the memory address 573: 492: 462: 377: 338: 334: 263: 110: 61: 3331: 1944: 1542:

feature was used to implement the Mask instruction, which was a logical

4505: 4463: 3043: 2489: 2316:. MIT Instrumentation Lab. July 11, 1963. p. Sheet 1 of 2, Note 2. 1975: 1926: 686: 671: 659: 485: 423: 258:. The computer's performance was comparable to the first generation of 252: 127: 3315: 1831:. It is believed to be responsible for problems emulating the LEM AGC 1768:

when referenced, would implement a certain function. For instance, an

839: 416: 408: 5808: 4520: 4485: 4450: 3947: 3863: 2997: 1997: 1721: 1688:—particularly for the design of more reliable systems that relied on 1442:

was triggered at regular intervals to update the user display (DSKY).

984: 565: 267: 1636:

The AGC had a sophisticated software interpreter, developed by the

1376: 400: 37: 2756:

Collins, Michael; Aldrin, Edwin (1975), Cortright, Edgar M. (ed.),

1664:, enforced proper transitions between native and interpreted code. 1497:

subsequence, had shifted 16 bits of uplink data into the AGC.

4978: 4510: 4480: 3952: 3375:

Restorers try to get lunar module guidance computer up and running

2967: 2548:"The History of Apollo On-board Guidance, Navigation, and Control" 1943: 1842: 1669: 1573: 1357:

subsequence which was repeated 6 times, and then terminated by an

838: 830: 818: 655: 651: 595: 522: 512: 415: 407: 399: 359: 351: 1546:

operation. Because the AGC had no native ability to do a logical

5842: 4990: 4910: 4500: 3566: 3337: 2689:"NASA Engineers and Scientists-Transforming Dreams Into Reality" 2363: 2087:

Journey to the Moon: The History of the Apollo Guidance Computer

629: 625: 3991: 3867: 3393: 1897:

alarm. After being given the "GO" from Houston, Aldrin entered

1720:

The Apollo Guidance Computer software influenced the design of

1401:

because the selected bank was determined by the bank register.

352: 4430: 4420: 3362: 2650:"Her Code Got Humans on the Moon—And Invented Software Itself" 1114:. Less than zero causes a skip to the third instruction after 2993:"AGC source code collection on Github, maintained by iBiblio" 2222:

Ramón Alonso, el argentino que llevó a la Apollo 11 a la Luna

1823:

instruction to enable them again). In the second action, the

1361:

subsequence. This was reduced to 3 subsequences in Block II.

1300:

of memory with register A and store the result in register A.

682:. This calculator-style interface was the first of its kind. 620:

It has an array of indicator lights, numeric displays, and a

1337:

Instructions were implemented in groups of 12 steps, called

693:

platform. The lunar module had a single DSKY for its AGC. A

2598:

AGC History Project (Caltech archive, original site closed)

2264:

AGC History Project (Caltech archive, original site closed)

2240:

AGC History Project (Caltech archive, original site closed)

2198:

AGC History Project (Caltech archive, original site closed)

2115:"Apollo Guidance, Navigation and Control Hardware Overview" 1039:

because they were accessed by performing a special type of

954:: Not a separate register, but the ones' complement of the 3221:

Lunar Module Attitude Controller Assembly Input Processing

2030:

More specifically, verb 16 instructs the AGC to print the

1921:

issued several "GO" calls and the landing was successful.

1243:. Whenever overflow is a possible but abnormal event, the 1239:

and control skips to the second instruction following the

918:: Not really a register, but the output of the adder (the 27:

Guidance and navigation computer used in Apollo spacecraft

2562: 2560: 1364:

Each timing pulse in a subsequence could trigger up to 5

1178:

specified by the operand of the instruction that follows

1050:

The Block I AGC instructions consisted of the following:

285:. Most of the software on the AGC is stored in a special 2900:, Breckenridge, Colorado: American Astronautical Society 2732:

The Apollo Guidance Computer: Architecture and Operation

2708:"13 minutes to the moon: Episode 5 The fourth astronaut" 2356:

Historical Studies in the Societal Impact of Spaceflight

1648:, scalar and vector arithmetic (16 and 24-bit), even an 987:, and 12 bits for address. Block I had 11 instructions: 465:, whose Herb Thaler was also on the architectural team. 1616:

consisting of the 'Exec', a batch job-scheduling using

1154:

ONE. A curious side effect was the creation and use of

1118:, and minus zero skips to the fourth instruction after 2388:"Apollo Guidance Computer and the First Silicon Chips" 1448:

was generated by various hardware failures or alarms.

1174:

can be used to add or subtract an index value to the

902:

arithmetic) or the increment to the program counter (

864:

ROM bank when addressing in the fixed-switchable mode

774:– the address of the next instruction to be executed 705:

The AGC timing reference came from a 2.048 MHz

5872: 5821: 5757: 5695: 5649: 5601: 5556: 5476: 5403: 5372: 5277: 5198: 5162: 5116: 5016: 4942: 4876: 4826: 4737: 4728: 4701: 4656: 4623: 4595: 4586: 4406: 4309: 4298: 4169: 4025: 3935: 3899: 3819: 3786: 3750: 3633: 3605: 3542: 3491: 3458: 3427: 3279:

Integrated Circuits in the Apollo Guidance Computer

3246:, for Command Module guidance computer. (nb. 83 Mb) 2839:Martin, Fred H. (July 1994), Jones, Eric M. (ed.), 1994:- the Apollo Primary Guidance and Navigation System 1776:instruction to return from an interrupt. Likewise, 723:The master frequency was further divided through a 217: 209: 201: 193: 185: 149: 141: 122: 103: 85: 67: 57: 47: 3240:, for Lunar Module guidance computer. (nb. 622 Mb) 3020:"Archiving and referencing the Apollo source code" 2060:Programmer's Manual, Block 2 AGC Assembly Language 1873:("Executive overflow - NO CORE SETS"), and then a 1558:was used to implement the equivalent of a logical 1230:Store register A at the specified memory address. 944:, and the lower bits (the address) were copied to 882:: 4-bit sequence register; the current instruction 827:. The AGC is opened up, showing its logic modules. 3334:– A web-based AGC simulator based on Virtual AGC. 1728:and early fly-by-wire fighter aircraft systems. 1102:skips to the first instruction immediately after 636:described the type of action to be performed and 368:Each lunar mission had two additional computers: 3572:Primary guidance, navigation, and control system 3228:) – By José Portillo Lugo, History of Technology 3150:Digital Apollo: Human and Machine in Spaceflight 2676:. NASA Office of Logic Design. February 3, 2010. 1566:through the bus, and then inverting the result. 1505:The AGC had a power-saving mode controlled by a 860:: 4-bit ROM bank register, to select the 1 293:, fashioned by weaving wires through and around 3261:Annotations to Eldon Hall's Journey to the Moon 2894:"Tales From The Lunar Module Guidance Computer" 2764:, Washington, DC: NASA, pp. Chapter 11.4, 2506:"Scene at MIT: Margaret Hamilton's Apollo code" 2423: 2421: 2419: 2417: 2415: 1676:The design principles developed for the AGC by 1130:to the beginning of the loop, equivalent to an 1064:instruction could be used for subroutine calls. 1717:for her role in creating the flight software. 1454:signaled a key press from the user's keyboard. 940:(containing the next op. code) were copied to 4003: 3879: 3690:Charged Particle Lunar Environment Experiment 3405: 3189:Computers in Spaceflight: The NASA Experience 2151:Computers in Spaceflight: The NASA Experience 1349:) used 8 subsequences: an initial one called 1081:. If all bits are set to one, this is called 429:welded to PCB in the Apollo guidance computer 8: 3216:) – By David Scott, Apollo mission astronaut 3174:Documentation on the AGC and its development 1952:The AGC formed the basis of an experimental 712:. The clock was divided by two to produce a 30: 5008:Computer performance by orders of magnitude 3252:National Air and Space Museum's AGC Block I 3209:The Apollo Guidance Computer - A Users View 3153:. Cambridge, Massachusetts: The MIT Press. 2898:27th annual Guidance and Control Conference 2814:Adler, Peter (1998), Jones, Eric M. (ed.), 2762:NASA SP-350, Apollo Expeditions to the Moon 2485:"Apollo DSKY panel relight: The full story" 2472:The Existential Graphs of Charles S. Peirce 2077: 2075: 511:, and the wiring was then embedded in cast 5473: 5113: 4734: 4592: 4306: 4010: 3996: 3988: 3886: 3872: 3864: 3412: 3398: 3390: 3120:"Apollo 11's source code is now on GitHub" 2648:Harvey IV, Harry Gould (13 October 2015). 2461:v. 4, paragraphs 12–20. Reprinted 1989 in 2000:(IBM S/360-derived) computers used in the 1811:instruction (the name is a contraction of 823:DSKY and AGC prototypes on display at the 749:for general computational use, called the 674:). Although data was stored internally in 36: 2735:. Springer Science & Business Media. 2582:. UK Metric Association. 18 October 2018. 843:Block II logic module, with flat-pack ICs 650:; these were driven by electromechanical 545:The computer had 2,048 words of erasable 3670:Apollo Lunar Surface Experiments Package 2919:. San Francisco: Condé Nast Publications 2147:"The Apollo guidance computer: Hardware" 1865:generated unanticipated warnings during 1784:instruction (inhibit interrupts), while 1760:flights, and was on board the ill-fated 1531:from the write bus into the S register. 1375: 592:Apollo computer DSKY user interface unit 587: 3285:Documentation of AGC software operation 3192:– By James Tomayko (Chapter 2, Part 5, 2566: 2541: 2539: 2537: 2528: 2050: 2023: 1275:, and elapsed time in triple precision. 835:Prototype logic module from Block I AGC 5951:Computer-related introductions in 1966 3695:Lunar Ejecta and Meteorites Experiment 3310:Some AGC-based projects and simulators 3234:– With comprehensive document archive 3194:The Apollo guidance computer: Hardware 2113:Interbartolo, Michael (January 2009). 1110:skips to the second instruction after 1047:) immediately before the instruction. 297:, though a small amount of read/write 29: 5961:Massachusetts Institute of Technology 3244:Colossus software source code listing 3238:Luminary software source code listing 2643: 2641: 1106:. If register A contained plus zero, 662:, and were typically used to display 568:word format was 14 bits of data, one 337:which was an Earth orbit mission and 7: 4979:Floating-point operations per second 3742:Suprathermal Ion Detector Experiment 3685:Apollo 14 Passive Seismic Experiment 3680:Apollo 12 Passive Seismic Experiment 2218:"Ramon Alonso's interview (Spanish)" 912:: The other ('y') input to the adder 3181:AGC4 Memo #9, Block II Instructions 2913:"Apollo 11: Mission Out of Control" 2620:(Press release). September 3, 2003. 1917:and his support team that included 1427:Interrupts and involuntary counters 898:(the adder was used to perform all 412:AGC dual 3-input NOR gate schematic 3712:Lunar Seismic Profiling Experiment 3700:Solar Wind Spectrometer Experiment 2553:. Charles Stark Draper Laboratory. 2314:"LOGIC MODULE ASSEMBLY NO. A1-A16" 695:flight director attitude indicator 482:Interplanetary Monitoring Platform 281:length, with 15 data bits and one 25: 5971:Spacecraft navigation instruments 3665:Solar Wind Composition Experiment 2864:Cortright, Edgar M., ed. (1975), 2841:"Apollo 11 : 25 Years Later" 2594:"Hugh Blair-Smith's Introduction" 2292:Rochester Institute of Technology 2224:, Diario La Nacion, March 7, 2010 1031:(extra). The first eight, called 922:sum of the contents of registers 262:from the late 1970s, such as the 243:that was installed on board each 42:Apollo Guidance Computer and DSKY 5905:Semiconductor device fabrication 3974: 3973: 3855:Category:Apollo program hardware 3850: 3849: 1589:AGC software was written in AGC 1538:ed onto the bus. This inclusive- 1477:The AGC also had 20 involuntary 1234:also detects, and corrects for, 156:15-bit wordlength + 1-bit parity 5880:History of general-purpose CPUs 4107:Nondeterministic Turing machine 3963:Universal Space Guidance System 3958:Launch Vehicle Digital Computer 3483:Launch Vehicle Digital Computer 3274:AGC Integrated Circuit Packages 2911:Witt, Stephen (June 24, 2019). 2892:Eyles, Don (February 6, 2004), 2870:Apollo 11 Lunar Surface Journal 2845:Apollo 11 Lunar Surface Journal 2820:Apollo 11 Lunar Surface Journal 714:four-phase 1.024 MHz clock 670:or a required velocity change ( 374:Launch Vehicle Digital Computer 52:Charles Stark Draper Laboratory 4060:Deterministic finite automaton 3773:Lunar Landing Research Vehicle 3653:Lunar Laser Ranging experiment 3623:Thermal Micrometeoroid Garment 3067:Collins, Keith (9 July 2016). 2546:Hoag, David (September 1976). 2504:Weinstock, Maia (2016-08-17). 2470:. See Roberts, Don D. (2009), 1807:The Block II AGC also has the 1678:MIT Instrumentation Laboratory 1638:MIT Instrumentation Laboratory 1271:, distances and velocities in 970:: Five 16-bit output registers 441:, with hardware design led by 435:MIT Instrumentation Laboratory 307:MIT Instrumentation Laboratory 1: 4851:Simultaneous and heterogenous 3732:Cold Cathode Gauge Experiment 3707:Modular Equipment Transporter 2729:O'Brien, Frank (2010-06-25). 2618:"NASA Honors Apollo Engineer" 2464:Writings of Charles S. Peirce 2393:National Air and Space Museum 2194:"Ramon Alonso's introduction" 2168:Agle, D.C. (September 1998). 1715:Presidential Medal of Freedom 1423:panel light was illuminated. 1296:Perform a bit-wise (boolean) 964:: Four 16-bit input registers 680:United States customary units 5535:Integrated memory controller 5517:Translation lookaside buffer 4716:Memory dependence prediction 4159:Random-access stored program 4112:Probabilistic Turing machine 3907:Apollo Abort Guidance System 3832:Rendezvous Docking Simulator 3643:Portable Life Support System 3552:Apollo Abort Guidance System 3344:AGC restarted 45 years later 3291:Delco Electronics, Apollo 15 2236:"Hugh Blair-Smith biography" 2012:History of computer hardware 1839:1201 and 1202 program alarms 1772:to address 25 triggered the 1680:, directed in late 1960s by 1514:time clock by 1.28 seconds. 433:The AGC was designed at the 380:booster instrumentation ring 4991:Synaptic updates per second 3979:Category:Guidance computers 3811:Apollo 11 goodwill messages 3369:Weaving the way to the Moon 3303:GitHub Complete Source Code 2866:"The Lunar Module Computer" 2632:"Virtual AGC Luminary Page" 1940:Applications outside Apollo 91:; 49 years ago 73:; 58 years ago 5992: 5956:Assembly language software 5395:Heterogeneous architecture 4317:Orthogonal instruction set 4087:Alternating Turing machine 4075:Quantum cellular automaton 3778:Mobile quarantine facility 3722:Lunar Surface Magnetometer 3365:Science Reporter – youtube 3147:Mindell, David A. (2008). 2938:Tomayko, James E. (2000), 2816:"Apollo 11 Program Alarms" 2260:"Herb Thaler introduction" 1610:real-time operating system 1431:The AGC had five vectored 1070:(count, compare, and skip) 798:: The lower product after 507:. They were connected via 5885:Microprocessor chronology 5848:Dynamic frequency scaling 5003:Cache performance metrics 3971: 3847: 3727:Lunar Traverse Gravimeter 3675:Active Seismic Experiment 3587:Descent propulsion system 2674:"About Margaret Hamilton" 2467:v. 4, pp. 218–21, Google 2145:James E. Tomayko (1988). 2089:, Reston, Virginia, USA: 1956:system installed into an 1869:, with the AGC showing a 1867:Apollo 11's lunar descent 1684:, became foundational to 1618:cooperative multi-tasking 1550:, but could do a logical 1087:diminished absolute value 780:: The remainder from the 764:, for general computation 678:, they were displayed as 600:LM DSKY interface diagram 501:resistor–transistor logic 499:, were implemented using 317:Astronauts manually flew 35: 5900:Hardware security module 5243:Digital signal processor 5220:Graphics processing unit 5032:Graphics processing unit 3917:Gemini Guidance Computer 3912:Apollo Guidance Computer 3717:Lunar Surface Gravimeter 3592:Ascent propulsion system 3567:Lunar Sounder Experiment 3562:Apollo Guidance Computer 3557:Apollo Docking Mechanism 3024:www.softwareheritage.org 2949:, Washington, D.C.: NASA 2758:"A Yellow Caution Light" 2266:, MIT, 14 September 2001 2007:Gemini Guidance Computer 745:The AGC had four 16-bit 333:, with the exception of 309:and first flew in 1966. 229:Apollo Guidance Computer 31:Apollo Guidance Computer 18:Apollo guidance computer 5946:Apollo program hardware 5853:Dynamic voltage scaling 5636:Memory address register 5530:Branch target predictor 5494:Address generation unit 5237:Physics processing unit 5026:Central processing unit 4985:Transactions per second 4973:Instructions per second 4896:Array processing (SIMT) 4040:Stored-program computer 3658:list of retroreflectors 3421:Apollo program hardware 3044:"Virtual AGC Home Page" 2947:The NASA History Series 2791:"chrislgarry/Apollo-11" 2600:, MIT, 30 November 2001 2428:Hall, Eldon C. (1972). 2398:Smithsonian Institution 1660:for an early prototype 894:: The 'x' input to the 825:Computer History Museum 616:and usually pronounced 497:Fairchild Semiconductor 213:70 lb (32 kg) 5966:1975 disestablishments 5659:Hardwired control unit 5541:Memory management unit 5506:Memory management unit 5255:Secure cryptoprocessor 5249:Tensor Processing Unit 5231:Vision processing unit 4965:Cycles per instruction 4959:Instructions per cycle 4906:Associative processing 4597:Instruction pipelining 4019:Processor technologies 3763:Launch Umbilical Tower 3577:Apollo Telescope Mount 2170:"Flying the Gusmobile" 2153:. NASA. Archived from 1949: 1859: 1586: 1385: 1190:A special instance of 1037:extracode instructions 844: 836: 828: 689:used for aligning the 601: 593: 527:diode–transistor logic 525:, which used a mix of 430: 413: 405: 365: 357: 5742:Sum-addressed decoder 5488:Arithmetic logic unit 4615:Classic RISC pipeline 4569:Epiphany architecture 4416:Motorola 68000 series 3518:Apollo service module 3504:Apollo command module 3377:(Wall Street Journal) 3326:Virtual AGC Home Page 3201:Computers Take Flight 2157:on December 29, 2023. 1947: 1846: 1690:asynchronous software 1640:, that implemented a 1626:pre-emptive scheduler 1577: 1379: 1227:(transfer to storage) 842: 834: 822: 784:instruction, and the 648:seven-segment display 599: 591: 535:universal logic gates 533:gates. NOR gates are 476:Following the use of 419: 411: 403: 385:Abort Guidance System 363: 355: 277:The AGC has a 16-bit 245:Apollo command module 205:AGC Assembly Language 5863:Performance per watt 5441:replacement policies 5107:Package on a package 4997:Performance per watt 4901:Pipelined processing 4671:Tomasulo's algorithm 4476:Clipper architecture 4332:Application-specific 4045:Finite-state machine 3900:On crewed spacecraft 3827:Lunar escape systems 3737:Heat Flow Experiment 3648:Lunar Roving Vehicle 2706:Fong, Kevin (2019). 2531:, pp. 154, 157. 2437:. Cambridge, MA: MIT 2366:. pp. 149–250. 2334:. NASA. May 22, 1963 2200:, MIT, July 27, 2001 1858:en route to the Moon 1686:software engineering 1599:magnetic-core memory 1218:(clear and subtract) 1043:instruction (called 666:such as space craft 614:display and keyboard 549:and 36,864 words of 547:magnetic-core memory 439:Charles Stark Draper 165:magnetic-core memory 5895:Digital electronics 5548:Instruction decoder 5500:Floating-point unit 5154:Soft microprocessor 5101:System in a package 4676:Reservation station 4206:Transport-triggered 3799:Lunar Flag Assembly 3768:Crawler-transporter 3523:Apollo Lunar Module 3382:Computer for Apollo 3358:Computer for Apollo 3232:The MIT AGC Project 2580:"The Moon landings" 2242:, MIT, January 2002 1976:Virtual AGC Project 1969:Source code release 1788:16 reenabled them ( 1694:priority scheduling 1556:De Morgan's theorem 1321:fixed-point numbers 608:to the AGC was the 427:integrated circuits 331:Apollo Lunar Module 256:integrated circuits 249:Apollo Lunar Module 32: 5941:Guidance computers 5767:Integrated circuit 5611:Processor register 5265:Baseband processor 4610:Operand forwarding 4070:Cellular automaton 3936:On launch vehicles 3894:Guidance computers 3204:– By James Tomayko 1950: 1934:J. Halcombe Laning 1901:again and another 1860: 1662:Christmas Computer 1614:J. Halcombe Laning 1587: 1386: 1247:was followed by a 1057:(transfer control) 1033:basic instructions 981:instruction format 845: 837: 829: 645:electroluminescent 602: 594: 480:(IC) chips in the 478:integrated circuit 447:architectural work 431: 414: 406: 366: 358: 131:integrated circuit 5928: 5927: 5817: 5816: 5436:Instruction cache 5426:Scratchpad memory 5273: 5272: 5260:Network processor 5189:Network on a chip 5144:Ultra-low-voltage 5095:Multi-chip module 4938: 4937: 4724: 4723: 4711:Branch prediction 4688:Register renaming 4582: 4581: 4564:VISC architecture 4386:Quantum computing 4381:VISC architecture 4263:Secondary storage 4179:Microarchitecture 4139:Register machines 3985: 3984: 3861: 3860: 3613:Apollo/Skylab A7L 3160:978-0-262-26668-0 3105:on 12 April 2021. 2742:978-1-4419-0877-3 2716:BBC World Service 2400:. 14 October 2015 2373:978-1-62683-027-1 1954:fly-by-wire (FBW) 1851:on the Apollo 11 1833:Luminary software 1707:Margaret Hamilton 1698:human-in-the-loop 1591:assembly language 1579:Margaret Hamilton 1353:, followed by an 808:editing locations 751:central registers 741:Central registers 691:inertial guidance 580:representation). 523:guidance computer 387:(AGS, pronounced 239:produced for the 225: 224: 194:Power consumption 115:Guidance computer 16:(Redirected from 5983: 5976:16-bit computers 5890:Processor design 5782:Power management 5664:Instruction unit 5525:Branch predictor 5474: 5172:System on a chip 5114: 4954:Transistor count 4878:Flynn's taxonomy 4735: 4593: 4396:Addressing modes 4307: 4253:Memory hierarchy 4117:Hypercomputation 4035:Abstract machine 4012: 4005: 3998: 3989: 3977: 3976: 3888: 3881: 3874: 3865: 3853: 3852: 3805:Fallen Astronaut 3597:Scimitar antenna 3582:Apollo TV camera 3414: 3407: 3400: 3391: 3164: 3135: 3134: 3132: 3131: 3116: 3110: 3106: 3101:. Archived from 3090: 3084: 3083: 3081: 3079: 3064: 3058: 3057: 3055: 3054: 3040: 3034: 3033: 3031: 3030: 3016: 3010: 3006: 3001:. Archived from 2989: 2983: 2982: 2980: 2978: 2963: 2957: 2956: 2955: 2954: 2944: 2935: 2929: 2928: 2926: 2924: 2908: 2902: 2901: 2889: 2880: 2879: 2878: 2877: 2861: 2855: 2854: 2853: 2852: 2836: 2830: 2829: 2828: 2827: 2811: 2805: 2804: 2802: 2801: 2787: 2781: 2780: 2779: 2778: 2753: 2747: 2746: 2726: 2720: 2719: 2703: 2697: 2696: 2695:on May 16, 2016. 2691:. Archived from 2684: 2678: 2677: 2670: 2664: 2663: 2661: 2660: 2645: 2636: 2635: 2628: 2622: 2621: 2614: 2608: 2607: 2606: 2605: 2590: 2584: 2583: 2576: 2570: 2564: 2555: 2554: 2552: 2543: 2532: 2526: 2520: 2519: 2517: 2516: 2501: 2495: 2494: 2481: 2475: 2458:Collected Papers 2453: 2447: 2446: 2444: 2442: 2436: 2425: 2410: 2409: 2407: 2405: 2384: 2378: 2377: 2361: 2350: 2344: 2343: 2341: 2339: 2324: 2318: 2317: 2310: 2304: 2303: 2301: 2299: 2289: 2280: 2274: 2273: 2272: 2271: 2256: 2250: 2249: 2248: 2247: 2232: 2226: 2225: 2214: 2208: 2207: 2206: 2205: 2190: 2184: 2183: 2181: 2180: 2165: 2159: 2158: 2142: 2136: 2135: 2134:. 11 March 2017. 2128: 2122: 2121: 2119: 2110: 2104: 2103: 2079: 2070: 2069: 2068: 2067: 2055: 2039: 2028: 1826: 1822: 1810: 1799: 1795: 1791: 1787: 1783: 1780:17 performed an 1779: 1775: 1771: 1651: 1399:fixed-switchable 1382:core rope memory 1360: 1356: 1352: 1348: 1329: 1315: 1305: 1293: 1287: 1280: 1273:double precision 1269:single precision 1266: 1262: 1258: 1254: 1250: 1246: 1242: 1233: 1226: 1217: 1211: 1203: 1197: 1193: 1187: 1181: 1173: 1167: 1158: 1153: 1149: 1145: 1141: 1137: 1129: 1125: 1121: 1117: 1113: 1109: 1105: 1101: 1097: 1075:ones' complement 1069: 1063: 1056: 1046: 1042: 1030: 1026: 1022: 1018: 1014: 1010: 1006: 1002: 998: 994: 990: 983:used 3 bits for 920:ones' complement 801: 791: 783: 718:master frequency 578:ones' complement 554:core rope memory 451:J. H. Laning Jr. 291:core rope memory 287:read-only memory 237:digital computer 176:core rope memory 99: 97: 92: 81: 79: 74: 71:August 1966 40: 33: 21: 5991: 5990: 5986: 5985: 5984: 5982: 5981: 5980: 5931: 5930: 5929: 5924: 5910:Tick–tock model 5868: 5824: 5813: 5753: 5737:Address decoder 5691: 5645: 5641:Program counter 5616:Status register 5597: 5552: 5512:Load–store unit 5479: 5472: 5399: 5368: 5269: 5226:Image processor 5201: 5194: 5164: 5158: 5134:Microcontroller 5124:Embedded system 5112: 5012: 4945: 4934: 4872: 4822: 4720: 4697: 4681:Re-order buffer 4652: 4633:Data dependency 4619: 4578: 4408: 4402: 4301: 4300:Instruction set 4294: 4280:Multiprocessing 4248:Cache hierarchy 4241:Register/memory 4165: 4065:Queue automaton 4021: 4016: 3986: 3981: 3967: 3943:ATHENA computer 3931: 3895: 3892: 3862: 3857: 3843: 3815: 3782: 3758:Mobile Launcher 3746: 3635: 3629: 3601: 3544: 3538: 3487: 3478:Instrument unit 3460: 3454: 3428:Launch vehicles 3423: 3418: 3351:Feature Stories 3338:Eagle Lander 3D 3171: 3161: 3146: 3143: 3138: 3129: 3127: 3118: 3117: 3113: 3092: 3091: 3087: 3077: 3075: 3066: 3065: 3061: 3052: 3050: 3042: 3041: 3037: 3028: 3026: 3018: 3017: 3013: 2991: 2990: 2986: 2976: 2974: 2965: 2964: 2960: 2952: 2950: 2942: 2937: 2936: 2932: 2922: 2920: 2910: 2909: 2905: 2891: 2890: 2883: 2875: 2873: 2863: 2862: 2858: 2850: 2848: 2838: 2837: 2833: 2825: 2823: 2813: 2812: 2808: 2799: 2797: 2789: 2788: 2784: 2776: 2774: 2772: 2755: 2754: 2750: 2743: 2728: 2727: 2723: 2705: 2704: 2700: 2686: 2685: 2681: 2672: 2671: 2667: 2658: 2656: 2647: 2646: 2639: 2630: 2629: 2625: 2616: 2615: 2611: 2603: 2601: 2592: 2591: 2587: 2578: 2577: 2573: 2565: 2558: 2550: 2545: 2544: 2535: 2527: 2523: 2514: 2512: 2503: 2502: 2498: 2493:. 27 July 2021. 2483: 2482: 2478: 2454: 2450: 2440: 2438: 2434: 2427: 2426: 2413: 2403: 2401: 2386: 2385: 2381: 2374: 2359: 2352: 2351: 2347: 2337: 2335: 2326: 2325: 2321: 2312: 2311: 2307: 2297: 2295: 2287: 2282: 2281: 2277: 2269: 2267: 2258: 2257: 2253: 2245: 2243: 2234: 2233: 2229: 2216: 2215: 2211: 2203: 2201: 2192: 2191: 2187: 2178: 2176: 2174:Air & Space 2167: 2166: 2162: 2144: 2143: 2139: 2130: 2129: 2125: 2117: 2112: 2111: 2107: 2101: 2093:, p. 196, 2081: 2080: 2073: 2065: 2063: 2057: 2056: 2052: 2048: 2043: 2042: 2029: 2025: 2020: 1988: 1971: 1942: 1841: 1824: 1820: 1808: 1797: 1793: 1789: 1785: 1781: 1777: 1773: 1769: 1749: 1741:Michael Collins 1696:, testing, and 1649: 1642:virtual machine 1572: 1524: 1507:standby allowed 1503: 1462:real-time clock 1429: 1374: 1358: 1354: 1350: 1346: 1327: 1313: 1303: 1291: 1285: 1278: 1264: 1260: 1256: 1255:is followed by 1252: 1248: 1244: 1240: 1231: 1224: 1215: 1209: 1201: 1195: 1191: 1185: 1179: 1171: 1165: 1156: 1151: 1147: 1143: 1139: 1135: 1127: 1123: 1119: 1115: 1111: 1107: 1103: 1099: 1095: 1067: 1061: 1054: 1044: 1040: 1028: 1024: 1020: 1016: 1012: 1008: 1004: 1000: 996: 992: 988: 977: 975:Instruction set 817: 815:Other registers 799: 789: 781: 772:program counter 743: 731:real-time clock 703: 612:, standing for 586: 543: 474: 398: 315: 181: 118: 95: 93: 90: 77: 75: 72: 43: 28: 23: 22: 15: 12: 11: 5: 5989: 5987: 5979: 5978: 5973: 5968: 5963: 5958: 5953: 5948: 5943: 5933: 5932: 5926: 5925: 5923: 5922: 5917: 5915:Pin grid array 5912: 5907: 5902: 5897: 5892: 5887: 5882: 5876: 5874: 5870: 5869: 5867: 5866: 5860: 5855: 5850: 5845: 5840: 5835: 5829: 5827: 5819: 5818: 5815: 5814: 5812: 5811: 5806: 5801: 5796: 5791: 5786: 5785: 5784: 5779: 5774: 5763: 5761: 5755: 5754: 5752: 5751: 5749:Barrel shifter 5746: 5745: 5744: 5739: 5732:Binary decoder 5729: 5728: 5727: 5717: 5712: 5707: 5701: 5699: 5693: 5692: 5690: 5689: 5684: 5676: 5671: 5666: 5661: 5655: 5653: 5647: 5646: 5644: 5643: 5638: 5633: 5628: 5623: 5621:Stack register 5618: 5613: 5607: 5605: 5599: 5598: 5596: 5595: 5594: 5593: 5588: 5578: 5573: 5568: 5562: 5560: 5554: 5553: 5551: 5550: 5545: 5544: 5543: 5532: 5527: 5522: 5521: 5520: 5514: 5503: 5497: 5491: 5484: 5482: 5471: 5470: 5465: 5460: 5455: 5450: 5449: 5448: 5443: 5438: 5433: 5428: 5423: 5413: 5407: 5405: 5401: 5400: 5398: 5397: 5392: 5387: 5382: 5376: 5374: 5370: 5369: 5367: 5366: 5365: 5364: 5354: 5349: 5344: 5339: 5334: 5329: 5324: 5319: 5314: 5309: 5304: 5299: 5294: 5289: 5283: 5281: 5275: 5274: 5271: 5270: 5268: 5267: 5262: 5257: 5252: 5246: 5240: 5234: 5228: 5223: 5217: 5215:AI accelerator 5212: 5206: 5204: 5196: 5195: 5193: 5192: 5186: 5181: 5178:Multiprocessor 5175: 5168: 5166: 5160: 5159: 5157: 5156: 5151: 5146: 5141: 5136: 5131: 5129:Microprocessor 5126: 5120: 5118: 5117:By application 5111: 5110: 5104: 5098: 5092: 5087: 5082: 5077: 5072: 5067: 5062: 5060:Tile processor 5057: 5052: 5047: 5042: 5041: 5040: 5029: 5022: 5020: 5014: 5013: 5011: 5010: 5005: 5000: 4994: 4988: 4982: 4976: 4970: 4969: 4968: 4956: 4950: 4948: 4940: 4939: 4936: 4935: 4933: 4932: 4931: 4930: 4920: 4915: 4914: 4913: 4908: 4903: 4898: 4888: 4882: 4880: 4874: 4873: 4871: 4870: 4865: 4860: 4855: 4854: 4853: 4848: 4846:Hyperthreading 4838: 4832: 4830: 4828:Multithreading 4824: 4823: 4821: 4820: 4815: 4810: 4809: 4808: 4798: 4797: 4796: 4791: 4781: 4780: 4779: 4774: 4764: 4759: 4758: 4757: 4752: 4741: 4739: 4732: 4726: 4725: 4722: 4721: 4719: 4718: 4713: 4707: 4705: 4699: 4698: 4696: 4695: 4690: 4685: 4684: 4683: 4678: 4668: 4662: 4660: 4654: 4653: 4651: 4650: 4645: 4640: 4635: 4629: 4627: 4621: 4620: 4618: 4617: 4612: 4607: 4605:Pipeline stall 4601: 4599: 4590: 4584: 4583: 4580: 4579: 4577: 4576: 4571: 4566: 4561: 4558: 4557: 4556: 4554:z/Architecture 4551: 4546: 4541: 4533: 4528: 4523: 4518: 4513: 4508: 4503: 4498: 4493: 4488: 4483: 4478: 4473: 4472: 4471: 4466: 4461: 4453: 4448: 4443: 4438: 4433: 4428: 4423: 4418: 4412: 4410: 4404: 4403: 4401: 4400: 4399: 4398: 4388: 4383: 4378: 4373: 4368: 4363: 4358: 4357: 4356: 4346: 4345: 4344: 4334: 4329: 4324: 4319: 4313: 4311: 4304: 4296: 4295: 4293: 4292: 4287: 4282: 4277: 4272: 4267: 4266: 4265: 4260: 4258:Virtual memory 4250: 4245: 4244: 4243: 4238: 4233: 4228: 4218: 4213: 4208: 4203: 4198: 4197: 4196: 4186: 4181: 4175: 4173: 4167: 4166: 4164: 4163: 4162: 4161: 4156: 4151: 4146: 4136: 4131: 4126: 4125: 4124: 4119: 4114: 4109: 4104: 4099: 4094: 4089: 4082:Turing machine 4079: 4078: 4077: 4072: 4067: 4062: 4057: 4052: 4042: 4037: 4031: 4029: 4023: 4022: 4017: 4015: 4014: 4007: 4000: 3992: 3983: 3982: 3972: 3969: 3968: 3966: 3965: 3960: 3955: 3950: 3945: 3939: 3937: 3933: 3932: 3930: 3929: 3924: 3919: 3914: 3909: 3903: 3901: 3897: 3896: 3893: 3891: 3890: 3883: 3876: 3868: 3859: 3858: 3848: 3845: 3844: 3842: 3841: 3834: 3829: 3823: 3821: 3817: 3816: 3814: 3813: 3808: 3801: 3796: 3790: 3788: 3784: 3783: 3781: 3780: 3775: 3770: 3765: 3760: 3754: 3752: 3751:Ground support 3748: 3747: 3745: 3744: 3739: 3734: 3729: 3724: 3719: 3714: 3709: 3704: 3703: 3702: 3697: 3692: 3687: 3682: 3677: 3667: 3662: 3661: 3660: 3650: 3645: 3639: 3637: 3631: 3630: 3628: 3627: 3626: 3625: 3620: 3609: 3607: 3603: 3602: 3600: 3599: 3594: 3589: 3584: 3579: 3574: 3569: 3564: 3559: 3554: 3548: 3546: 3540: 3539: 3537: 3536: 3535: 3534: 3533: 3532: 3520: 3515: 3514: 3513: 3495: 3493: 3489: 3488: 3486: 3485: 3480: 3475: 3470: 3464: 3462: 3459:Launch vehicle 3456: 3455: 3453: 3452: 3447: 3442: 3437: 3431: 3429: 3425: 3424: 3419: 3417: 3416: 3409: 3402: 3394: 3388: 3387: 3378: 3372: 3366: 3348: 3347: 3341: 3335: 3329: 3323: 3312: 3311: 3307: 3306: 3300: 3294: 3287: 3286: 3282: 3281: 3276: 3270: 3269: 3265: 3264: 3258: 3249: 3248: 3247: 3241: 3229: 3217: 3205: 3197: 3185: 3176: 3175: 3170: 3169:External links 3167: 3166: 3165: 3159: 3142: 3139: 3137: 3136: 3126:. 10 July 2016 3111: 3093:Garry, Chris. 3085: 3059: 3035: 3011: 3005:on 7 May 2021. 2984: 2958: 2930: 2903: 2881: 2856: 2831: 2806: 2782: 2771:978-0486471754 2770: 2748: 2741: 2721: 2698: 2679: 2665: 2637: 2623: 2609: 2585: 2571: 2569:, p. 149. 2556: 2533: 2521: 2496: 2476: 2448: 2411: 2379: 2372: 2345: 2319: 2305: 2275: 2251: 2227: 2209: 2185: 2160: 2137: 2123: 2105: 2099: 2083:Hall, Eldon C. 2071: 2049: 2047: 2044: 2041: 2040: 2022: 2021: 2019: 2016: 2015: 2014: 2009: 2004: 1995: 1987: 1984: 1970: 1967: 1941: 1938: 1840: 1837: 1813:Ed's Interrupt 1748: 1745: 1733:Neil Armstrong 1703:Richard Battin 1682:Charles Draper 1593:and stored on 1583:Apollo Project 1571: 1568: 1523: 1520: 1502: 1499: 1485:), decrement ( 1472: 1471: 1465: 1455: 1449: 1443: 1428: 1425: 1373: 1370: 1366:control pulses 1335: 1334: 1331: 1325: 1317: 1311: 1307: 1301: 1294: 1289: 1282: 1276: 1228: 1222: 1219: 1213: 1205: 1199: 1188: 1183: 1168: 1163: 1071: 1065: 1058: 976: 973: 972: 971: 965: 959: 949: 931: 913: 907: 900:1's complement 889: 883: 877: 871: 865: 855: 816: 813: 804: 803: 793: 786:return address 775: 765: 742: 739: 702: 699: 606:user interface 585: 584:DSKY interface 582: 542: 539: 473: 472:Logic hardware 470: 459:Richard Battin 455:Albert Hopkins 397: 394: 393: 392: 381: 376:(LVDC) on the 327:command module 323:control sticks 319:Project Gemini 314: 311: 301:is available. 295:magnetic cores 260:home computers 241:Apollo program 223: 222: 219: 215: 214: 211: 207: 206: 203: 199: 198: 195: 191: 190: 187: 183: 182: 180: 179: 168: 157: 153: 151: 147: 146: 143: 139: 138: 124: 120: 119: 117: 116: 113: 107: 105: 101: 100: 89:July 1975 87: 83: 82: 69: 65: 64: 59: 55: 54: 49: 45: 44: 41: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 5988: 5977: 5974: 5972: 5969: 5967: 5964: 5962: 5959: 5957: 5954: 5952: 5949: 5947: 5944: 5942: 5939: 5938: 5936: 5921: 5918: 5916: 5913: 5911: 5908: 5906: 5903: 5901: 5898: 5896: 5893: 5891: 5888: 5886: 5883: 5881: 5878: 5877: 5875: 5871: 5864: 5861: 5859: 5856: 5854: 5851: 5849: 5846: 5844: 5841: 5839: 5836: 5834: 5831: 5830: 5828: 5826: 5820: 5810: 5807: 5805: 5802: 5800: 5797: 5795: 5792: 5790: 5787: 5783: 5780: 5778: 5775: 5773: 5770: 5769: 5768: 5765: 5764: 5762: 5760: 5756: 5750: 5747: 5743: 5740: 5738: 5735: 5734: 5733: 5730: 5726: 5723: 5722: 5721: 5718: 5716: 5713: 5711: 5710:Demultiplexer 5708: 5706: 5703: 5702: 5700: 5698: 5694: 5688: 5685: 5683: 5680: 5677: 5675: 5672: 5670: 5667: 5665: 5662: 5660: 5657: 5656: 5654: 5652: 5648: 5642: 5639: 5637: 5634: 5632: 5631:Memory buffer 5629: 5627: 5626:Register file 5624: 5622: 5619: 5617: 5614: 5612: 5609: 5608: 5606: 5604: 5600: 5592: 5589: 5587: 5584: 5583: 5582: 5579: 5577: 5574: 5572: 5569: 5567: 5566:Combinational 5564: 5563: 5561: 5559: 5555: 5549: 5546: 5542: 5539: 5538: 5536: 5533: 5531: 5528: 5526: 5523: 5518: 5515: 5513: 5510: 5509: 5507: 5504: 5501: 5498: 5495: 5492: 5489: 5486: 5485: 5483: 5481: 5475: 5469: 5466: 5464: 5461: 5459: 5456: 5454: 5451: 5447: 5444: 5442: 5439: 5437: 5434: 5432: 5429: 5427: 5424: 5422: 5419: 5418: 5417: 5414: 5412: 5409: 5408: 5406: 5402: 5396: 5393: 5391: 5388: 5386: 5383: 5381: 5378: 5377: 5375: 5371: 5363: 5360: 5359: 5358: 5355: 5353: 5350: 5348: 5345: 5343: 5340: 5338: 5335: 5333: 5330: 5328: 5325: 5323: 5320: 5318: 5315: 5313: 5310: 5308: 5305: 5303: 5300: 5298: 5295: 5293: 5290: 5288: 5285: 5284: 5282: 5280: 5276: 5266: 5263: 5261: 5258: 5256: 5253: 5250: 5247: 5244: 5241: 5238: 5235: 5232: 5229: 5227: 5224: 5221: 5218: 5216: 5213: 5211: 5208: 5207: 5205: 5203: 5197: 5190: 5187: 5185: 5182: 5179: 5176: 5173: 5170: 5169: 5167: 5161: 5155: 5152: 5150: 5147: 5145: 5142: 5140: 5137: 5135: 5132: 5130: 5127: 5125: 5122: 5121: 5119: 5115: 5108: 5105: 5102: 5099: 5096: 5093: 5091: 5088: 5086: 5083: 5081: 5078: 5076: 5073: 5071: 5068: 5066: 5063: 5061: 5058: 5056: 5053: 5051: 5048: 5046: 5043: 5039: 5036: 5035: 5033: 5030: 5027: 5024: 5023: 5021: 5019: 5015: 5009: 5006: 5004: 5001: 4998: 4995: 4992: 4989: 4986: 4983: 4980: 4977: 4974: 4971: 4966: 4963: 4962: 4960: 4957: 4955: 4952: 4951: 4949: 4947: 4941: 4929: 4926: 4925: 4924: 4921: 4919: 4916: 4912: 4909: 4907: 4904: 4902: 4899: 4897: 4894: 4893: 4892: 4889: 4887: 4884: 4883: 4881: 4879: 4875: 4869: 4866: 4864: 4861: 4859: 4856: 4852: 4849: 4847: 4844: 4843: 4842: 4839: 4837: 4834: 4833: 4831: 4829: 4825: 4819: 4816: 4814: 4811: 4807: 4804: 4803: 4802: 4799: 4795: 4792: 4790: 4787: 4786: 4785: 4782: 4778: 4775: 4773: 4770: 4769: 4768: 4765: 4763: 4760: 4756: 4753: 4751: 4748: 4747: 4746: 4743: 4742: 4740: 4736: 4733: 4731: 4727: 4717: 4714: 4712: 4709: 4708: 4706: 4704: 4700: 4694: 4691: 4689: 4686: 4682: 4679: 4677: 4674: 4673: 4672: 4669: 4667: 4666:Scoreboarding 4664: 4663: 4661: 4659: 4655: 4649: 4648:False sharing 4646: 4644: 4641: 4639: 4636: 4634: 4631: 4630: 4628: 4626: 4622: 4616: 4613: 4611: 4608: 4606: 4603: 4602: 4600: 4598: 4594: 4591: 4589: 4585: 4575: 4572: 4570: 4567: 4565: 4562: 4559: 4555: 4552: 4550: 4547: 4545: 4542: 4540: 4537: 4536: 4534: 4532: 4529: 4527: 4524: 4522: 4519: 4517: 4514: 4512: 4509: 4507: 4504: 4502: 4499: 4497: 4494: 4492: 4489: 4487: 4484: 4482: 4479: 4477: 4474: 4470: 4467: 4465: 4462: 4460: 4457: 4456: 4454: 4452: 4449: 4447: 4444: 4442: 4441:Stanford MIPS 4439: 4437: 4434: 4432: 4429: 4427: 4424: 4422: 4419: 4417: 4414: 4413: 4411: 4405: 4397: 4394: 4393: 4392: 4389: 4387: 4384: 4382: 4379: 4377: 4374: 4372: 4369: 4367: 4364: 4362: 4359: 4355: 4352: 4351: 4350: 4347: 4343: 4340: 4339: 4338: 4335: 4333: 4330: 4328: 4325: 4323: 4320: 4318: 4315: 4314: 4312: 4308: 4305: 4303: 4302:architectures 4297: 4291: 4288: 4286: 4283: 4281: 4278: 4276: 4273: 4271: 4270:Heterogeneous 4268: 4264: 4261: 4259: 4256: 4255: 4254: 4251: 4249: 4246: 4242: 4239: 4237: 4234: 4232: 4229: 4227: 4224: 4223: 4222: 4221:Memory access 4219: 4217: 4214: 4212: 4209: 4207: 4204: 4202: 4199: 4195: 4192: 4191: 4190: 4187: 4185: 4182: 4180: 4177: 4176: 4174: 4172: 4168: 4160: 4157: 4155: 4154:Random-access 4152: 4150: 4147: 4145: 4142: 4141: 4140: 4137: 4135: 4134:Stack machine 4132: 4130: 4127: 4123: 4120: 4118: 4115: 4113: 4110: 4108: 4105: 4103: 4100: 4098: 4095: 4093: 4090: 4088: 4085: 4084: 4083: 4080: 4076: 4073: 4071: 4068: 4066: 4063: 4061: 4058: 4056: 4053: 4051: 4050:with datapath 4048: 4047: 4046: 4043: 4041: 4038: 4036: 4033: 4032: 4030: 4028: 4024: 4020: 4013: 4008: 4006: 4001: 3999: 3994: 3993: 3990: 3980: 3970: 3964: 3961: 3959: 3956: 3954: 3951: 3949: 3946: 3944: 3941: 3940: 3938: 3934: 3928: 3925: 3923: 3920: 3918: 3915: 3913: 3910: 3908: 3905: 3904: 3902: 3898: 3889: 3884: 3882: 3877: 3875: 3870: 3869: 3866: 3856: 3846: 3840: 3839: 3835: 3833: 3830: 3828: 3825: 3824: 3822: 3818: 3812: 3809: 3807: 3806: 3802: 3800: 3797: 3795: 3792: 3791: 3789: 3785: 3779: 3776: 3774: 3771: 3769: 3766: 3764: 3761: 3759: 3756: 3755: 3753: 3749: 3743: 3740: 3738: 3735: 3733: 3730: 3728: 3725: 3723: 3720: 3718: 3715: 3713: 3710: 3708: 3705: 3701: 3698: 3696: 3693: 3691: 3688: 3686: 3683: 3681: 3678: 3676: 3673: 3672: 3671: 3668: 3666: 3663: 3659: 3656: 3655: 3654: 3651: 3649: 3646: 3644: 3641: 3640: 3638: 3634:Lunar surface 3632: 3624: 3621: 3619: 3616: 3615: 3614: 3611: 3610: 3608: 3604: 3598: 3595: 3593: 3590: 3588: 3585: 3583: 3580: 3578: 3575: 3573: 3570: 3568: 3565: 3563: 3560: 3558: 3555: 3553: 3550: 3549: 3547: 3541: 3531: 3530: 3526: 3525: 3524: 3521: 3519: 3516: 3512: 3511: 3507: 3506: 3505: 3502: 3501: 3500: 3497: 3496: 3494: 3490: 3484: 3481: 3479: 3476: 3474: 3471: 3469: 3466: 3465: 3463: 3457: 3451: 3448: 3446: 3443: 3441: 3438: 3436: 3435:Little Joe II 3433: 3432: 3430: 3426: 3422: 3415: 3410: 3408: 3403: 3401: 3396: 3395: 3392: 3385: 3383: 3379: 3376: 3373: 3370: 3367: 3364: 3360: 3359: 3355: 3354: 3353: 3352: 3345: 3342: 3339: 3336: 3333: 3330: 3327: 3324: 3321: 3317: 3314: 3313: 3309: 3308: 3304: 3301: 3298: 3295: 3292: 3289: 3288: 3284: 3283: 3280: 3277: 3275: 3272: 3271: 3267: 3266: 3262: 3259: 3257: 3253: 3250: 3245: 3242: 3239: 3236: 3235: 3233: 3230: 3227: 3223: 3222: 3218: 3215: 3211: 3210: 3206: 3203: 3202: 3198: 3195: 3191: 3190: 3186: 3183: 3182: 3178: 3177: 3173: 3172: 3168: 3162: 3156: 3152: 3151: 3145: 3144: 3140: 3125: 3121: 3115: 3112: 3109: 3104: 3100: 3096: 3089: 3086: 3074: 3070: 3063: 3060: 3049: 3045: 3039: 3036: 3025: 3021: 3015: 3012: 3009: 3004: 3000: 2999: 2994: 2988: 2985: 2973: 2969: 2966:Burkey, Ron. 2962: 2959: 2948: 2941: 2934: 2931: 2923:September 18, 2918: 2914: 2907: 2904: 2899: 2895: 2888: 2886: 2882: 2871: 2867: 2860: 2857: 2846: 2842: 2835: 2832: 2821: 2817: 2810: 2807: 2796: 2792: 2786: 2783: 2773: 2767: 2763: 2759: 2752: 2749: 2744: 2738: 2734: 2733: 2725: 2722: 2717: 2713: 2709: 2702: 2699: 2694: 2690: 2687:A.J.S. Rayl. 2683: 2680: 2675: 2669: 2666: 2655: 2651: 2644: 2642: 2638: 2633: 2627: 2624: 2619: 2613: 2610: 2599: 2595: 2589: 2586: 2581: 2575: 2572: 2568: 2563: 2561: 2557: 2549: 2542: 2540: 2538: 2534: 2530: 2525: 2522: 2511: 2507: 2500: 2497: 2492: 2491: 2486: 2480: 2477: 2473: 2469: 2466: 2465: 2460: 2459: 2452: 2449: 2433: 2432: 2424: 2422: 2420: 2418: 2416: 2412: 2399: 2395: 2394: 2389: 2383: 2380: 2375: 2369: 2365: 2358: 2357: 2349: 2346: 2333: 2329: 2323: 2320: 2315: 2309: 2306: 2293: 2286: 2279: 2276: 2265: 2261: 2255: 2252: 2241: 2237: 2231: 2228: 2223: 2219: 2213: 2210: 2199: 2195: 2189: 2186: 2175: 2171: 2164: 2161: 2156: 2152: 2148: 2141: 2138: 2133: 2127: 2124: 2116: 2109: 2106: 2102: 2100:1-56347-185-X 2096: 2092: 2088: 2084: 2078: 2076: 2072: 2062: 2061: 2054: 2051: 2045: 2037: 2033: 2027: 2024: 2017: 2013: 2010: 2008: 2005: 2003: 2002:Space Shuttle 1999: 1996: 1993: 1990: 1989: 1985: 1983: 1981: 1977: 1968: 1966: 1964: 1963:Space Shuttle 1959: 1955: 1946: 1939: 1937: 1935: 1931: 1928: 1922: 1920: 1916: 1912: 1908: 1904: 1900: 1896: 1892: 1888: 1882: 1880: 1876: 1872: 1868: 1864: 1857: 1856: 1853:Lunar Module 1850: 1845: 1838: 1836: 1834: 1830: 1818: 1814: 1805: 1803: 1765: 1763: 1759: 1755: 1746: 1744: 1742: 1738: 1734: 1729: 1727: 1726:Space Shuttle 1723: 1718: 1716: 1712: 1708: 1704: 1699: 1695: 1691: 1687: 1683: 1679: 1674: 1671: 1665: 1663: 1659: 1655: 1647: 1646:trigonometric 1643: 1639: 1634: 1632: 1631:metric system 1627: 1623: 1619: 1615: 1611: 1606: 1604: 1600: 1596: 1592: 1584: 1580: 1576: 1569: 1567: 1565: 1561: 1557: 1553: 1549: 1545: 1541: 1537: 1532: 1528: 1521: 1519: 1515: 1511: 1508: 1500: 1498: 1494: 1492: 1489:), or shift ( 1488: 1484: 1480: 1475: 1469: 1466: 1463: 1459: 1456: 1453: 1450: 1447: 1444: 1441: 1438: 1437: 1436: 1434: 1426: 1424: 1422: 1416: 1412: 1410: 1405: 1402: 1400: 1396: 1392: 1383: 1378: 1371: 1369: 1367: 1362: 1344: 1340: 1339:timing pulses 1332: 1326: 1322: 1318: 1312: 1308: 1302: 1299: 1295: 1290: 1283: 1277: 1274: 1270: 1237: 1229: 1223: 1220: 1214: 1206: 1200: 1189: 1184: 1177: 1169: 1164: 1160: 1133: 1092: 1088: 1084: 1080: 1076: 1072: 1066: 1059: 1053: 1052: 1051: 1048: 1038: 1034: 1019:(basic), and 986: 982: 974: 969: 966: 963: 960: 957: 953: 950: 947: 943: 939: 935: 932: 929: 925: 921: 917: 914: 911: 908: 905: 901: 897: 893: 890: 887: 884: 881: 878: 875: 872: 869: 866: 863: 859: 856: 853: 850: 849: 848: 841: 833: 826: 821: 814: 812: 809: 797: 794: 787: 779: 776: 773: 769: 766: 763: 759: 756: 755: 754: 752: 748: 740: 738: 736: 732: 728: 727: 721: 719: 715: 711: 708: 700: 698: 696: 692: 688: 683: 681: 677: 673: 669: 665: 661: 657: 653: 649: 646: 641: 639: 635: 631: 627: 623: 619: 615: 611: 607: 598: 590: 583: 581: 579: 575: 572:bit, and one 571: 567: 563: 559: 555: 552: 548: 540: 538: 536: 532: 528: 524: 521: 516: 514: 510: 506: 502: 498: 494: 489: 487: 483: 479: 471: 469: 466: 464: 460: 456: 452: 448: 444: 443:Eldon C. Hall 440: 436: 428: 425: 422: 418: 410: 402: 395: 390: 386: 382: 379: 375: 371: 370: 369: 362: 354: 350: 348: 344: 340: 336: 332: 328: 324: 320: 312: 310: 308: 302: 300: 296: 292: 288: 284: 280: 275: 273: 272:Commodore PET 269: 265: 261: 257: 254: 250: 246: 242: 238: 234: 230: 220: 216: 212: 208: 204: 200: 196: 192: 188: 184: 177: 173: 170:36,864 words 169: 166: 162: 158: 155: 154: 152: 148: 144: 140: 136: 132: 129: 125: 121: 114: 112: 109: 108: 106: 102: 88: 84: 70: 66: 63: 60: 56: 53: 50: 46: 39: 34: 19: 5920:Chip carrier 5858:Clock gating 5777:Mixed-signal 5674:Write buffer 5651:Control unit 5463:Clock signal 5306: 5202:accelerators 5184:Cypress PSoC 4841:Simultaneous 4658:Out-of-order 4290:Neuromorphic 4171:Architecture 4129:Belt machine 4122:Zeno machine 4055:Hierarchical 3911: 3836: 3803: 3794:Lunar plaque 3561: 3527: 3508: 3381: 3357: 3350: 3349: 3220: 3208: 3200: 3193: 3188: 3180: 3149: 3128:. Retrieved 3123: 3114: 3103:the original 3098: 3088: 3076:. Retrieved 3072: 3062: 3051:. Retrieved 3047: 3038: 3027:. Retrieved 3023: 3014: 3003:the original 2996: 2987: 2975:. Retrieved 2971: 2968:"VirtualAGC" 2961: 2951:, retrieved 2946: 2933: 2921:. Retrieved 2916: 2906: 2897: 2874:, retrieved 2869: 2859: 2849:, retrieved 2844: 2834: 2824:, retrieved 2819: 2809: 2798:. Retrieved 2794: 2785: 2775:, retrieved 2761: 2751: 2731: 2724: 2711: 2701: 2693:the original 2682: 2668: 2657:. Retrieved 2653: 2626: 2612: 2602:, retrieved 2597: 2588: 2574: 2567:Mindell 2008 2529:Mindell 2008 2524: 2513:. Retrieved 2509: 2499: 2488: 2479: 2471: 2462: 2456: 2451: 2439:. Retrieved 2430: 2402:. Retrieved 2391: 2382: 2355: 2348: 2336:. Retrieved 2331: 2322: 2308: 2296:. Retrieved 2291: 2278: 2268:, retrieved 2263: 2254: 2244:, retrieved 2239: 2230: 2221: 2212: 2202:, retrieved 2197: 2188: 2177:. Retrieved 2173: 2163: 2155:the original 2150: 2140: 2126: 2108: 2086: 2064:, retrieved 2059: 2053: 2035: 2031: 2026: 1992:Apollo PGNCS 1972: 1958:F-8 Crusader 1951: 1932: 1923: 1910: 1906: 1902: 1898: 1894: 1890: 1886: 1883: 1879:cycle steals 1874: 1870: 1861: 1854: 1829:lunar module 1812: 1806: 1802:far pointers 1766: 1750: 1730: 1719: 1711:person-years 1675: 1666: 1661: 1657: 1635: 1612:designed by 1607: 1588: 1563: 1559: 1551: 1547: 1543: 1539: 1535: 1533: 1529: 1525: 1516: 1512: 1506: 1504: 1501:Standby mode 1495: 1490: 1486: 1482: 1476: 1473: 1467: 1457: 1451: 1445: 1439: 1430: 1421:parity alarm 1420: 1417: 1413: 1409:memory cycle 1408: 1406: 1403: 1398: 1394: 1390: 1387: 1365: 1363: 1342: 1338: 1336: 1297: 1176:base address 1155: 1090: 1086: 1082: 1078: 1049: 1036: 1032: 978: 967: 961: 955: 951: 945: 941: 937: 933: 927: 923: 915: 909: 903: 895: 891: 885: 879: 873: 867: 857: 851: 846: 807: 805: 802:instructions 795: 792:instructions 777: 767: 757: 750: 744: 734: 724: 722: 717: 704: 684: 676:metric units 642: 637: 633: 617: 613: 609: 603: 544: 520:Minuteman II 517: 490: 475: 467: 432: 388: 367: 346: 343:Apollo PGNCS 316: 303: 276: 232: 228: 226: 133:(IC) chips ( 86:Discontinued 58:Manufacturer 5705:Multiplexer 5669:Data buffer 5380:Single-core 5352:bit slicing 5210:Coprocessor 5065:Coprocessor 4946:performance 4868:Cooperative 4858:Speculative 4818:Distributed 4777:Superscalar 4762:Instruction 4730:Parallelism 4703:Speculative 4535:System/3x0 4407:Instruction 4184:Von Neumann 4097:Post–Turing 3838:Moon Museum 3606:Space suits 3320:AGC Replica 3316:AGC Replica 3297:Source code 3048:ibiblio.org 2404:1 September 2338:19 February 2332:Archive.org 2294:. p. 9 1919:Jack Garman 1915:Steve Bales 1849:Buzz Aldrin 1737:Buzz Aldrin 1595:rope memory 1395:fixed-fixed 1343:subsequence 762:accumulator 531:diode logic 503:(RTL) in a 299:core memory 159:2048 words 48:Invented by 5935:Categories 5825:management 5720:Multiplier 5581:Logic gate 5571:Sequential 5478:Functional 5458:Clock rate 5431:Data cache 5404:Components 5385:Multi-core 5373:Core count 4863:Preemptive 4767:Pipelining 4750:Bit-serial 4693:Wide-issue 4638:Structural 4560:Tilera ISA 4526:MicroBlaze 4496:ETRAX CRIS 4391:Comparison 4236:Load–store 4216:Endianness 3927:IBM AP-101 3787:Ceremonial 3618:Beta cloth 3545:components 3543:Spacecraft 3492:Spacecraft 3473:J-2 engine 3468:F-1 engine 3461:components 3371:(BBC News) 3130:2021-09-09 3053:2021-09-09 3029:2021-09-09 2953:2009-09-01 2876:2010-02-04 2851:2009-09-01 2826:2009-09-01 2800:2016-07-17 2777:2009-08-30 2659:2018-11-25 2604:2010-03-21 2515:2016-08-17 2270:2009-08-30 2246:2009-08-30 2204:2009-08-30 2179:2018-12-15 2066:2018-08-27 2046:References 1980:MIT Museum 1875:1201 alarm 1871:1202 alarm 1522:Data buses 1433:interrupts 1330:(subtract) 1306:(multiply) 1204:(exchange) 1091:Diminished 1083:minus zero 858:Bank/Fbank 622:calculator 618:"DIS-kee". 564:-internal 558:parity bit 488:IC chips. 449:came from 283:parity bit 218:Dimensions 68:Introduced 5759:Circuitry 5679:Microcode 5603:Registers 5446:coherence 5421:CPU cache 5279:Word size 4944:Processor 4588:Execution 4491:DEC Alpha 4469:Power ISA 4285:Cognitive 4092:Universal 3636:equipment 3445:Saturn IB 3386:– youtube 3346:– youtube 3078:19 August 2712:bbc.co.uk 2474:, p. 131. 2298:29 August 1847:DSKY and 1817:Ed Smally 1654:the 1960s 1622:interrupt 1620:, and an 1608:A simple 1603:Apollo 14 1236:overflows 1079:plus zero 906:register) 747:registers 551:read-only 515:plastic. 509:wire wrap 505:flat-pack 313:Operation 289:known as 247:(CM) and 145:2.048 MHz 142:Frequency 126:Discrete 123:Processor 5697:Datapath 5390:Manycore 5362:variable 5200:Hardware 4836:Temporal 4516:OpenRISC 4211:Cellular 4201:Dataflow 4194:modified 3922:IBM TC-1 3510:Columbia 3450:Saturn V 3440:Saturn I 3124:Engadget 2977:10 April 2510:MIT News 2085:(1996), 1986:See also 1927:synchros 1885:command 1815:, after 1762:Apollo 1 1754:Apollo 4 1747:Block II 1624:-driven 1570:Software 1479:counters 1316:(divide) 958:register 862:kiloword 668:attitude 574:sign bit 570:overflow 493:NOR gate 463:Raytheon 445:. Early 421:Flatpack 378:Saturn V 339:Apollo 8 335:Apollo 7 329:and the 264:Apple II 235:) was a 202:Language 111:Avionics 62:Raytheon 5873:Related 5804:Quantum 5794:Digital 5789:Boolean 5687:Counter 5586:Quantum 5347:512-bit 5342:256-bit 5337:128-bit 5180:(MPSoC) 5165:on chip 5163:Systems 4981:(FLOPS) 4794:Process 4643:Control 4625:Hazards 4511:Itanium 4506:Unicore 4464:PowerPC 4189:Harvard 4149:Pointer 4144:Counter 4102:Quantum 3820:Related 3499:Apollo 3361:(1965) 3141:Sources 3108:Alt URL 3008:Alt URL 2972:iBiblio 2490:YouTube 2441:15 June 1796:called 1458:T3Rrupt 1452:Keyrupt 1132:IBM 360 1085:.) The 735:standby 707:crystal 687:sextant 672:delta-V 664:vectors 660:decimal 486:silicon 424:silicon 253:silicon 128:silicon 96:1975-07 94: ( 78:1966-08 76: ( 5809:Switch 5799:Analog 5537:(IMC) 5508:(MMU) 5357:others 5332:64-bit 5327:48-bit 5322:32-bit 5317:24-bit 5312:16-bit 5307:15-bit 5302:12-bit 5139:Mobile 5055:Stream 5050:Barrel 5045:Vector 5034:(GPU) 4993:(SUPS) 4961:(IPC) 4813:Memory 4806:Vector 4789:Thread 4772:Scalar 4574:Others 4521:RISC-V 4486:SuperH 4455:Power 4451:MIPS-X 4426:PDP-11 4275:Fabric 4027:Models 3948:ASC-15 3332:Moonjs 3157: 3099:GitHub 3073:Quartz 2998:GitHub 2872:, NASA 2847:, NASA 2822:, NASA 2795:GitHub 2768: 2739: 2370: 2097: 1998:AP-101 1821:RESUME 1809:EDRUPT 1798:EXTEND 1790:RELINT 1782:INHINT 1774:RESUME 1722:Skylab 1468:Uprupt 1440:Dsrupt 1372:Memory 1259:ZERO ( 1186:RESUME 1162:holes. 1159:-holes 1126:and a 1045:EXTEND 1027:, and 1015:, and 985:opcode 788:after 770:: The 760:: The 737:mode. 726:scaler 701:Timing 652:relays 628:, and 566:16-bit 560:. The 541:Memory 437:under 396:Design 270:, and 268:TRS-80 210:Weight 150:Memory 137:based) 5865:(PPW) 5823:Power 5715:Adder 5591:Array 5558:Logic 5519:(TLB) 5502:(FPU) 5496:(AGU) 5490:(ALU) 5480:units 5416:Cache 5297:8-bit 5292:4-bit 5287:1-bit 5251:(TPU) 5245:(DSP) 5239:(PPU) 5233:(VPU) 5222:(GPU) 5191:(NoC) 5174:(SoC) 5109:(PoP) 5103:(SiP) 5097:(MCM) 5038:GPGPU 5028:(CPU) 5018:Types 4999:(PPW) 4987:(TPS) 4975:(IPS) 4967:(CPI) 4738:Level 4549:S/390 4544:S/370 4539:S/360 4481:SPARC 4459:POWER 4342:TRIPS 4310:Types 3529:Eagle 3384:video 2943:(PDF) 2917:Wired 2654:WIRED 2551:(PDF) 2435:(PDF) 2360:(PDF) 2288:(PDF) 2118:(PDF) 2018:Notes 1863:PGNCS 1855:Eagle 1825:ZRUPT 1786:INDEX 1778:INDEX 1770:INDEX 1670:octal 1491:Shinc 1446:Erupt 1384:(ROM) 1310:sign. 1281:(add) 1196:INDEX 1192:INDEX 1180:INDEX 1172:INDEX 1166:INDEX 1150:*+2, 1146:*+2, 997:INDEX 896:adder 874:Sbank 868:Ebank 710:clock 656:octal 513:epoxy 347:pings 321:with 186:Ports 5843:ACPI 5576:Glue 5468:FIFO 5411:Core 5149:ASIP 5090:CPLD 5085:FPOA 5080:FPGA 5075:ASIC 4928:SPMD 4923:MIMD 4918:MISD 4911:SWAR 4891:SIMD 4886:SISD 4801:Data 4784:Task 4755:Word 4501:M32R 4446:MIPS 4409:sets 4376:ZISC 4371:NISC 4366:OISC 4361:MISC 4354:EPIC 4349:VLIW 4337:EDGE 4327:RISC 4322:CISC 4231:HUMA 4226:NUMA 3953:D-17 3256:Dsky 3254:and 3155:ISBN 3080:2016 2979:2021 2925:2019 2766:ISBN 2737:ISBN 2443:2021 2406:2019 2368:ISBN 2364:NASA 2340:2024 2300:2023 2095:ISBN 2091:AIAA 2036:0668 2032:noun 1978:and 1911:1668 1907:1668 1903:1202 1899:1668 1895:1202 1891:1668 1887:1668 1756:and 1739:and 1629:the 1487:Minc 1483:Pinc 1391:Bank 1380:AGC 1292:MASK 1142:was 1017:MASK 979:The 926:and 638:Noun 634:Verb 630:Noun 626:Verb 610:DSKY 604:The 529:and 383:the 372:The 279:word 227:The 197:55 W 104:Type 5838:APM 5833:PMU 5725:CPU 5682:ROM 5453:Bus 5070:PAL 4745:Bit 4531:LMC 4436:ARM 4431:x86 4421:VAX 3363:MIT 3226:PDF 3214:PDF 1658:YUL 1650:MXV 1560:AND 1548:AND 1544:AND 1359:MP3 1355:MP1 1351:MP0 1298:and 1265:XCH 1261:CAF 1257:CAF 1202:XCH 1157:CCS 1140:CCS 1136:BCT 1134:'s 1124:CCS 1120:CCS 1116:CCS 1112:CCS 1108:CCS 1104:CCS 1100:CCS 1096:CCS 1068:CCS 1001:XCH 993:CCS 968:OUT 658:or 562:CPU 389:ags 233:AGC 172:ROM 161:RAM 135:RTL 5937:: 5772:3D 3122:. 3097:. 3071:. 3046:. 3022:. 2995:. 2970:. 2945:, 2915:. 2896:, 2884:^ 2868:, 2843:, 2818:, 2793:. 2760:, 2714:. 2710:. 2652:. 2640:^ 2596:, 2559:^ 2536:^ 2508:. 2487:. 2414:^ 2396:. 2390:. 2362:. 2330:. 2290:. 2262:, 2238:, 2220:, 2196:, 2172:. 2149:. 2074:^ 1835:. 1804:. 1794:TC 1764:. 1743:. 1735:, 1724:, 1692:, 1605:. 1564:OR 1552:OR 1540:OR 1536:OR 1435:: 1347:MP 1328:SU 1314:DV 1304:MP 1286:AD 1279:AD 1263:= 1253:TS 1249:TC 1245:TS 1241:TS 1232:TS 1225:TS 1216:CS 1210:TS 1152:AD 1148:TC 1144:TC 1128:TC 1062:TC 1055:TC 1041:TC 1029:DV 1025:MP 1023:, 1021:SU 1013:AD 1011:, 1009:TS 1007:, 1005:CS 1003:, 999:, 995:, 991:, 989:TC 962:IN 942:SQ 880:SQ 800:MP 796:LP 790:TC 782:DV 753:: 632:. 457:, 453:, 349:. 274:. 266:, 4011:e 4004:t 3997:v 3887:e 3880:t 3873:v 3413:e 3406:t 3399:v 3322:. 3224:( 3212:( 3196:) 3163:. 3133:. 3082:. 3056:. 3032:. 2981:. 2927:. 2803:. 2745:. 2718:. 2662:. 2634:. 2518:. 2445:. 2408:. 2376:. 2342:. 2302:. 2182:. 2120:. 1758:6 1585:. 1464:. 1212:. 1194:( 956:B 952:C 948:. 946:S 938:B 934:B 930:) 928:Y 924:X 916:U 910:Y 904:Z 892:X 886:G 852:S 778:Q 768:Z 758:A 576:( 231:( 178:) 174:( 167:) 163:( 98:) 80:) 20:)

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

Index