Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!ll-xn!cit-vax!tybalt.caltech.edu!walton From: walton@tybalt.caltech.edu (Steve Walton) Newsgroups: comp.sys.amiga Subject: Re: XMODEM Message-ID: <3280@cit-vax.Caltech.Edu> Date: Mon, 20-Jul-87 12:33:07 EDT Article-I.D.: cit-vax.3280 Posted: Mon Jul 20 12:33:07 1987 Date-Received: Tue, 21-Jul-87 05:11:15 EDT References: <8707200126.AA15199@cogsci.berkeley.edu> Sender: news@cit-vax.Caltech.Edu Reply-To: walton@tybalt.caltech.edu.UUCP (Steve Walton) Organization: Calfornia Institute of Technology Lines: 26 In article <8707200126.AA15199@cogsci.berkeley.edu> bryce@COGSCI.BERKELEY.EDU (Bryce Nesbitt) writes: >I have several different terminal emulator programs for the Amiga. All support >XMODEM transfer. Only one supports XMODEM CRC. XMODEM CRC is *EASY* to add, >and gives a big reliability boost for transfer over noisy lines. I'd like to >have this feature on all the programs I use, and to this end I have dug up >the actual specification for XMODEM and XMODEM CRC. While we're wish-listing for terminal programs, here's mine in order of importance: (1) Kermit--the single best protocol for communication between heterogenous machines. The basic protocol can be implemented with very few lines. Also has options for 1-byte checkum, or 2 or 3-byte CRC's. (2) Long packet XMODEM--same as normal XMODEM but with 1024-byte packets. A big win over packet switched networks. CRC nearly mandatory here. (3) Batch XMODEM, sometimes called YMODEM--Simple: interpret the first 128-byte packet you receive as containing a null-terminated file name. Also contains the exact length of the file in bytes--no more chopping! Optionally contains file mod date and mode. (4) Windowed protocol, Kermit (hard) or WXMODEM (somewhat easier)--These are full duplex protocols which simultaneously send data both ways. I find 1200 baud WXMODEM achieves an 1150 baud transfer rate over good ol' Telenet. Steve Walton, guest as walton@tybalt.caltech.edu AMETEK Computer Research Division, ametek!walton@csvax.caltech.edu "Long signatures are definitely frowned upon"--USENET posting rules