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265:, prior to his death. He ran data transmission software company Omen Technology which he founded in 1984. Omen Technology published software tools such as ZComm (a terminal-based communications program that included the ZMODEM-90 file transfer protocol) and DSZ. He was an
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Forsberg then wrote a version, Zmodem G, which was for use over "guaranteed error free" communications lines, such as
Ethernet or short serial-to-serial computer connections. This protocol waived the usual retransmission overhead, to send files as fast as possible.
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of the underlying link. ZMODEM could also resume interrupted transfers without retransmitting the already-received blocks. In addition to developing the protocol, Forsberg developed
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219:. Rather than wait for positive acknowledgment after each block is sent, it sends blocks in rapid succession and resends unacknowledged blocks later. By avoiding delays due to
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Originally, he wrote a program for Unix called rbsb (receive batch / send batch) which used block 0 to transmit a file's name, and optionally date and time, since
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after "Modem.asm", the original version of Xmodem released by
Christensen in the CP/M User's group in 1977.
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407:"Image of software diskettes for ZComm and DSZ, software products published by Omen Software (circa 1990)"
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to start at block 1, leaving block 0 available. Christensen suggested
Forsberg call his protocol
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Diskette images for Omen
Technology's ZComm and DSZ products (circa 1989–1990)
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because it was "one better" than Xmodem. Forsberg created the program
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Rebels on the Air: An
Alternative History of Radio in America
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373:. Archived from the original on September 15, 2015
269:(call sign WA7KGX) and a licensed aircraft pilot.
202:Dvorak Award for Excellence in Telecommunications
184:(May 6, 1944 – September 24, 2015) developed two
170:Dvorak Award for Excellence in Telecommunications
421:"Amateur License – WA7KGX – FORSBERG, CHARLES A"
391:: CS1 maint: bot: original URL status unknown (
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231:for sending and receiving files using ZMODEM.
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283:cited Forsberg as a participant in WMAS, a
208:. He was also the project engineer on the
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295:. He graduated from the academy in 1962.
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316:"Obituary of Charles Alton Forsberg"
188:protocols popular in the 1990s, for
261:Forsberg most recently resided in
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215:The widely adopted ZMODEM uses a
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182:Charles Alton "Chuck" Forsberg
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502:American electrical engineers
497:American computer programmers
212:-series graphics terminals.
16:American computer programmer
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318:. Crown Memorial Centers
289:Western Military Academy
371:"About Omen Technology"
217:sliding window protocol
204:in 1992 for developing
99:University of Wisconsin
507:Aviators from Illinois
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267:amateur radio operator
198:bulletin board systems
88:Electrical engineering
25:Charles Alton Forsberg
454:. pp. 199, 305.
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492:Amateur radio people
285:pirate radio station
140:Computer engineering
196:files from dial-up
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130:Engineering career
56:September 24, 2015
45:Wilmette, Illinois
461:978-0-8147-9381-7
256:Yet Another Modem
186:data transmission
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105:Years active
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344:. Archived from
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263:Portland, Oregon
240:Ward Christensen
200:. He received a
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72:Other names
64:Portland, Oregon
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95:Alma mater
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424:. Retrieved
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375:. Retrieved
350:. Retrieved
346:the original
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320:. Retrieved
281:Jesse Walker
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114:Notable work
58:(2015-09-24)
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487:2015 deaths
482:1944 births
352:December 8,
194:downloading
146:Employer(s)
41:May 6, 1944
476:Categories
322:August 19,
299:References
136:Discipline
37:1944-05-06
452:NYU Press
242:designed
225:bandwidth
190:uploading
150:Tektronix
80:Education
444:(2001).
387:cite web
229:software
156:Projects
221:latency
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248:YMODEM
244:XMODEM
206:ZMODEM
166:Awards
123:ZMODEM
119:YMODEM
108:1968–?
90:(1968)
456:ISBN
428:2012
393:link
379:2012
354:2010
324:2022
192:and
84:M.S.
66:, US
53:Died
47:, US
31:Born
291:in
287:at
252:YAM
478::
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389:}}
385:{{
362:^
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307:^
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
