M3SE LS-DOS (TRS-80 Model 4) system and development files

The files in these archives, even the text files, should be copied to the TRS-80 Model 4/4D/4P in binary transfer mode.

Don't attempt to copy every file in the archive; just update the ones that are listed in the change log below. Otherwise you might overwrite open system files, or cause files that require fixed locations on the disk or in the directory to be moved. If any such file ever needs an update I'll provide instructions.

Most of the system files are password-protected, so you should run FTPD with the "-b" (bypass passwords) switch.

You should expect that files listed under archives with dates later than when you ordered your M3SE should be updated. Copy them from the latest archive.

M3SE1.0_lsdos_sys_2016_11_05.zip M3SE 1.x November 5, 2016 M3SE LS-DOS system files from CF drive :0
M3SE1.0_lsdos_dev_2016_11_05.zip M3SE 1.x November 5, 2016 M3SE LS-DOS development files from CF drive :1

Change Log (since original March 20, 2016 release):


  1. ARGS/REL: Re-fixed a pre-production bug where the command line gets modified by the application, preventing <CTRL>-R from working properly.


  1. FTP/CMD: Re-linked with updated ARGS/REL. Fixed a bug in command-line <BREAK> handling. Version number to 0.4.1.
  2. FTPD/CMD: Re-linked with updated ARGS/REL. Version number to 0.4.1.
  3. PING/CMD: Re-linked with updated ARGS/REL. No version number.
  4. TELNET/CMD: Re-linked with updated ARGS/REL. Version number to 0.5.1.


  1. ACCESS/JCL: Added FTP/CMD and PING/CMD, see below.
  2. FTP/CMD: Added FTP client, version 0.4.
  3. FTPD/CMD: Improved handling of data socket errors. Version numbers to 0.4.
  4. NETWORK/CFG: Added [FTP Client] section with default settings.
  5. PING/CMD: Added.
  6. TELNET/CMD: Cursor-related fixes. Fixed a bug where argument buffer could overflow on command-line input. Version number to 0.5.


  1. ARGS/ASM: Added ARGS_ALT subroutine to allow alternate ARGV buffer.
  2. ARGS/REL: New ARGS_ALT subroutine, see above. Both calls now zero out ARGV array at start.
  3. DNSHOST/REL, DNSLOOK/REL: DNS_CLOSE and DNS_HCLOSE subroutines don't affect CPU flags.
  4. NETWORK/REL: Improved randomization of source port numbers in IP_SPORT subroutine.

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