September 10, 2010 – New Downloads thanks to Vernon B Hester

September 10, 2010 – New Downloads thanks to Vernon B Hester

Vernon B. Hester, author of MultiDOS and other wonderful programs, has provided some additional copies of his DOS’s:

Esoteric DOS v2.11 for Model 4
MultiDOS v4.01 for Model I
MultiDOS v4.01 for Model III
MultiDOS v5.11 for Model 4

ESOTERIC is a Model 4 version of MULTIDOS with two differences: Video (Esoteric is 80×24 vs. MultiDOS which is either 80×24 or 64×16) and ESOTERIC is mapped significantly different than Model 4 MULTIDOS. The mapping of the Model 4 is very similar to the Model I, Model III, and MAX-80 version of MULTIDOS, while ESOTERIC’s mapping difference was desired to keep the DOS in contiguous memory (0000H through 1AFFH) allowing one to ORG applications at 1B00H.


  1. Very cool. I was playing with this on TRS32. Watch out for running the emulator sped up, although this is prob. true for any emulator. Running DDT – disk drive timer … the simple things. 🙂

  2. Does anyone else have a problem running any of the utility disk CMD’s using TRS32? I’ve got the esot-u.dmk inserted as DISK 1 and esot-s.dmk in DISK 0 but when I try to run program on the utility disk I keep getting a “Drive configuration error.”

  3. Long answer: The System diskette is one-sided and the Utility diskette is two-sided (to get everything onto one diskette). Therefore, one must either:
    1) key CONFIG [:]1 (SI=2)
    This configures RAM to handle the diskette in drive 1 as two-sided (SIdes = 2)
    2) perform CAT [:]1
    This automatically configures RAM to the configuration of the diskette in drive 1. This enables MULTIDOS/ESOTERIC to display the directory on
    any ‘normal’ TRS-80 diskette – including NeWDOS80 and Model I single-density TRSDOS.

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