New DMK Utility Thanks to Quentin Barnes

May 13, 2021 – New DMK Utility Thanks to Quentin Barnes

Quentin Barnes was kind enough to write a utility I had been seeking for quite some time, to be used in conjunction with reading DMK’s (such as on a Cateasel).

Called DMKBSC, the utility runs under LINUX and under MSDOS (just like CW2DMK), and will parse a DMK and advise as to which specific sectors which are bad, if any.

For those who read floppy disks into DMK format, this utility, in conjunction with SuperUtility or other disk mapping software, can tell you what file resided on a bad sector, so you can know what data, if any, was actually lost.

A Tarball with binaries of v0.0.1 can be downloaded here and the source code can be downloaded here.

Update: George Philips was kind enough to compile for Windows x64, so for those that would like that version it can be found, packaged with the MSDOS and LINUX binaries, here.

BOOTSTRAP Updated to v7.6 + Mobile Phone as Player

Jürgen Büssert continues his development of the BOOTSTRAP utility, which now permits people without boot diskettes to create them from a cassette based Model I, III, or 4 system. His page can be found here as can v7.6 of his software.

He has also expanded the cassette player abilities to a mobile phone, so those with a mobile phone and an appropriate TRS-80 DIN plug can make boot disks by playing the BOOTSTRAP input files on a mobile phone. Details on this can be found here.

Two New Model III ROM CRC’s

The international version of TRSDOS v1.3 for the Model III reports two previously unknown ‘valid’ CRC’s for ROM C: 3BE7 and 10A6. If anyone out there has a ROM C with those CRC’s a dump (which can be accomplished with a BASIC program) would be greatly appreciated!

Catweasel Tools Updated to v4.7

Quentin Barnes has released v4.7 of the Catweasel Tools originally written by Tim Mann.


  • Added -C option to cw2dmk for controlling detection of incompatibly formatted sides of a floppy disk. If side 1 is formatted with 512-byte sectors and side 0 is formatted with any other sector size, it’ll assume side 1 was factory-formatted and skip it. Detection of other incompatible combinations may be added in a future release. Use “-C 0” to disable the detection.
  • Added new interactive menu. When enabled with -Mi and the interrupt key is pressed (typically ^C), cw2dmk will enter a menu with options. Also, -Me will enable dropping into the menu when the error limit for a track exceeds the number set by -x.
  • Deprecated cw2dmk’s -b option introduced in 4.6.0. It had too many shortcomings with CP/M disks. Replaced with -C.

You can download from Github..

Various New and Different Items!

  • Pete Cetinski has released his game RoundUp! for purchase on disk and on tape. He is using eBay for ordering, so if you are interested, please visit his auctions!
  • George Philips has written a Model III Game where you try to free the stuck Ever Given from the canal. You can download it here or play it via online emulator here.
  • Amardeep Chana has written a Tape-Based Disk Formatter for the TRS-80 Model III or 4. It will allow you to exercise the floppy drives without a bootable diskette. You can download v1.2 here.
  • Lawrence Kesteloot appears to have updated the command line version of his cassette reader/cleaner utility on April 25, 2021. You can download it from
  • Jürgen Büssert has updated his Tape-Based DOS Maker for the Model I to v4.1. You can find his web page explaining operation here or you can download the file here.