This is not my own compilation, but the one from David Keil.
His site is gone, but most data is still present in the WayBack machine

This page is a simplified version of David Keil's DOS page. I added the ZIP files, contents listings and some archives.
TRS-80 Model 1/III/4/4P
- Disk Operating Systems Page -
Last updated on April 8, 2005

 

CP/M Plus
Version 01.00.00
RS Catalog # 26-2216 / Copyright 1983

Model RAM Size
Model 4 64k - 128k 247k
Contents

    Length      Date    Time    Name
---------  ---------- -----   ----
   256016  1999-09-14 14:45   DRCPM-1.DSK  unbanked BIOS
   256016  1999-09-14 15:09   DRCPM-2.DSK  banked BIOS
   256016  1999-09-14 14:54   DRCPM-3.DSK  standard utilities
   256016  1999-09-14 14:56   DRCPM-4.DSK  help disk
   256016  1999-09-14 15:09   DRCPM-5.DSK  assembly sources, backrest 

26-2216.ace (corrupted) / cpmpls3.zip

CP/M
Version 1.42 - Version 2.22 - Version 2.31
by Montezuma Micro

Model RAM Size
Model 4 64k - 128k 288k & 352k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
21.03.99 20:38       92244    512016   18%  CPM142.DSK                    
01.08.99 15:26       52080    256016   20%  CPM222.DSK                    
25.09.00 14:33       28176    256016   11%  MMCPM231.DSK                  
25.09.00 15:17       47516    256016   18%  MMRSHD.DSK                    
25.09.00 14:33       43900    256016   17%  MMTOOLS.DSK                   
25.09.00 14:34       30172    256016   11%  MMWINDOW.DSK                  

96-0001.ace / 96-0001.zip

DOSPLUS (Model 1/3)
Version 3.50
by Micro-Systems Software, Inc.

Model RAM Size
Model 1/III/4 16k -48k 74k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
21.04.99 00:50       62320    256016   24%  DOSPLS35.DSK                  
22.09.00 13:26       10412    114256    9%  DOSP35B.DSK                   
22.09.00 13:26        2044    114256    1%  DOSP35A.DSK                   

96-0010.ace / 96-0010.zip

DOSPLUS (Model 4/4P)
Version 1.0
by Micro-Systems Software, Inc.

Model RAM Size
Model 4 16k - 128k 33k
Contents

  Date    Time     Packed      Size  Ratio  File
   202240  1980-08-29 12:00   dp4v185a.dsk
   202240  1980-08-29 12:00   dp4v185b.dsk

   256016  2003-04-18 19:30   DSP4HARD.DSK

96-0011.ace (corrupted) / DosPlus M4 1985-01 / DosPlus M4 Harddisk Drivers

Double DOS
Version 4.20 - Version 4.23
by Percom Data

Model RAM Size
Model 1 16k - 48k 26k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
12.08.99 02:29       25268    492816    5%  DBDOS423.DSK                  
12.08.99 02:19         440    256016    0%  DBDOS420.DSK                  

96-0007.ace / 96-0007.zip

LDOS (Model 1 & 3)
Version 5.3.1
by Misosys, Inc.

Model RAM Size
Model 1/III/4 16k - 48k 121k
Model 1 Hard Disk Driver & Utilities
(Single Density LDOS virtual disk)
This disk contains drivers and utilities for using Radio Shack hard drives with LDOS on a real TRS-80 Model 1 or the emulator.
RSHARD1/CMD WD1010 HDC driver. Will control 1 to 2 drives of up to 1024 cylinders and 8 heads. Allows partitioning of HD into logical drives based on cylinder and head.
When using this driver with the emulator, use the 'R' parameter when entering device number (ex. 1R) to instruct the driver that the HD is removable.
RSFORM1/CMD WD1010 HDC format utility to use with RSHARD1/DCT.
RSFORM1A/CMD WD1010 HDC format utility to use with RSHARD1/DCT. This version has been modified to put the directory on cylinder 1.
To quickly format a virtual HD on the emulator use the command:

RSFORM1A (SYSTEM=YES,VERIFY=NO)
Model 3 Hard Disk Driver & Utilities
(Double Density LDOS virtual disk)
This disk contains drivers and utilities for using Radio Shack hard drives with LDOS on a real TRS-80 Model III/4 or the emulator.
RSHARD5/CMD WD1010 HDC driver. Will control 1 to 2 drives of up to 1024 cylinders and 8 heads. Allows partitioning of HD into logical drives based on cylinder and head.
When using this driver with the emulator, use the 'R' parameter when entering device number (ex. 1R) to instruct the driver that the HD is removable.
RSFORM5/CMD WD1010 HDC format utility to use with RSHARD5/DCT.
RSFORM5A/CMD WD1010 HDC format utility to use with RSHARD5/DCT. This version has been modified to put the directory on cylinder 1.
To quickly format a virtual HD on the emulator use the command:

RSFORM5A (SYSTEM=YES,VERIFY=NO)
ARCHIVE5/CMD
RESTORE5/CMD
Hard disk utility to backup and restore files to large to fit onto a single floppy disk
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
29.04.99 01:46       88984    256016   34%  LD3-531.DSK                   
28.07.99 22:19        8780    114256    7%  LD351-2.DSK                   
28.07.99 22:19       13360    114256   11%  LD351-1.DSK                   
25.03.00 17:10        6484    130576    5%  MOD1HARD.DSK                  
15.03.00 14:35        5172    256016    2%  MOD3HARD.DSK

96-0003.ace / 96-0003.zip

LS-DOS (Model 4/4P)
Version 6.3.1
by Misosys, Inc.

Model RAM Size
Model 4 64k - 128k 124k
Hard Disk Driver & Utilities
(Double Density LDOS virtual disk)
This disk contains drivers and utilities for using Radio Shack hard drives with LS-DOS on a real TRS-80 Model 4/4P or the emulator.
TRSHD6/DCT WD1010 HDC driver. Will control 1 to 4 drives of up to 406 cylinders and 8 heads. Allows partitioning of HD into logical drives based on head.
TRSFORM6/CMD WD1010 HDC format utility to use with TRSHD6/DCT.
TRSFRM6A/CMD WD1010 HDC format utility to use with TRSHD6/DCT. This version has been modified to put the directory on cylinder 1.
To quickly format a virtual HD on the emulator use the command:

TRSFRM6A (SYSTEM=YES,VERIFY=NO)
RSHARD6/CMD WD1010 HDC driver. Will control 1 to 2 drives of up to 1024 cylinders and 8 heads. Allows partitioning of HD into logical drives based on cylinder and head.
When using this driver with the emulator, use the 'R' parameter when entering device number (ex. 1R) to instruct the driver that the HD is removable.
RSFORM6/CMD WD1010 HDC format utility to use with RSHARD6/DCT.
RSFORM6A/CMD WD1010 HDC format utility to use with RSHARD6/DCT. This version has been modified to put the directory on cylinder 1.
To quickly format a virtual HD on the emulator use the command:

RSFORM6A (SYSTEM=YES,VERIFY=NO)
ARCHIVE6/CMD
RESTORE6/CMD
Hard disk utility to backup and restore files to large to fit onto a single floppy disk
HDBT2/TXT
HDBOOT/FIX
HDSYS0/FIX
Instructions and patch files for making a HD, with LS-DOS 6.3.1 loaded on it, bootable on a 4P (emulator 4P too).
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
16.07.99 08:44      109716    505616   21%  LD4-631.DSK                   
15.03.00 14:25       16364    256016    6%  MOD4HARD.DSK                  

96-0004.ace / 96-0004.zip

MULTIDOS (Model 1/3)
Version 1.5SK - Version 1.6

by Cosmopolitan Elec. Corp.

Model RAM Size
Model 1/III/4 16k - 48k 64k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
01.08.99 14:14       20400    130576   15%  MDOS15.DSK                    
25.02.99 18:38       44664    256016   17%  MULTIDOS.DSK

96-0012.ace / 96-0012.zip

MULTIDOS (Model 4/4P)
Version 2.10

by Cosmopolitan Elec. Corp.

Model RAM Size
Model 4 64k - 128k 89k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
25.03.99 19:05       90608    256016   35%  MULTI4-M.DSK                  

96-0013.ace / 96-0013.zip

NewDOS/80
Version 2.0 - Version 2.5
by Apparat, Inc.

Model RAM Size
Model 1/III/4 16k - 48k 110k

NewDOS/80 Hard Disk Support
Version 2.5

Version 2.5 of NewDOS/80 has limited support of hard disks. The Model 1 .ZIP contains v2.0 & v2.5. I have not found v2.5 for the Model 3/4 yet.

Appendix C of the user's manual gives instructions on how to setup a hard disk.

Model 4P bootable NEWDOS/80

The Model 4P versions of NEWDOS/80 have a special MODELA/III ROM image file that allows them to boot on the Model 4P. The 4P versions will boot on a Model III, 4 or 4P system.

The MODELA/III file is the standard TRSDOS v6.xx file that has been padded and placed on the NEWDOS/80 disk so it aligns with LDOS's six sector/granule structure. The file also has 3 sectors of a LDOS DIR/SYS embedded in it so that it aligns with a real track boundary.

The 3rd byte of sector 1 on track 0 (boot sector) has been modified to point to the embedded LDOS directory in the MODELA/III file. This byte is not used by NEWDOS/80 since it uses the 3rd byte of sector 0 to find the directory lump. During a Model 4P boot this byte is used to find the directory track of an LDOS disk, search for the MODELA/III file entry and then load the MODELA/III file. Pointing the 3rd byte at the embedded LDOS directory allows the 4P to find the MODELA/III file and load it.

The 4P version of NEWDOS/80 can be used almost exactly like the regular version of NEWDOS/80, but because of the exact placement of the MODELA/III file on the 4P disk and the 1 byte modification of the boot sector certain guidelines must be obeyed or the original disk or its copies will be unbootable on a Model 4P.

  • The MODELA/III cannot be modified, deleted, moved or recopied onto the NEWDOS/80 4P disk. Doing so will result in the disk being only Model 3/4 bootable.

  • The MODELA/III files on the single & double sided 4P disks are not the same and because of the padding and embedded LDOS directory are not compatible with other DOSs. However, the actual ROM image that is loaded, is.

  • To make a 4P bootable copy use a type 5 copy using the BDU option, example:
    COPY 0,1,,BDU
    You can use this method to make a real Model 4P boot disk in a compatible PC drive.

  • Copying the 4P NEWDOS/80 disk to a disk of a different configuration by using a type 6 copy will result in the disk being only Model 3/4 bootable.

Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
25.02.00 05:08       67280    512016   13%  ND80-M3.DSK                   
25.02.00 05:09       14036    512016    2%  ND80-4PD.DSK                  
25.02.00 05:09        1724    256016    0%  ND80-4PS.DSK                  
25.02.00 05:06       14024    130576   10%  ND80-M1.DSK                   
19.01.05 14:01       14324    114256   12%  ND80-HD1.DSK

96-0005.ace / 96-0005.zip

NewDOS/86 - 90
Version 1.0
by Apparat, Inc. & W.S. (Warwick) Sands and D.S. Sands

Model RAM Size
Model 1/III 16k - 48k -

NewDOS/86 - 90

NewDos86/90 is the result of extending the well known NewDos/80v2 operating system for the Tandy TRS-80 model 1, model 3 and model 4 computers. It is developed by W.S. (Warwick) Sands and D.S. Sands. between 1984 and 1990. Worldwide distribution was done by Computer News 80 in the U.S.A.

The project started with additions to the Disk Basic but later extended to the operating system. Some of the most striking are:

  • A timestamp is stored for each file in the directory. Shown by DIR B
  • The DIR, COPY and PURGE commands now supports a wildcard syntax. This can be applied on the filename, extension and the date. In short:
  • . start of filename anchor
  • / start of extension anchor
  • - negate operator
  • < upper limit ASCII value or date
  • > lower limit ASCII value or date
  • @ one character wildcard
  • ? zero or one characher wildcard
  • * zero or more character wildcard
  • Automatic PDRIVE recognition
  • PDRIVE extension with SPG (sectors per ganule). This allows reading and writing of double density diskettes made by other DOSses.
  • 29 new SYSTEM parameters. These include printer control, type ahead buffer, loading routines in high memory, and more.
  • A simple command line calculator at the prompt
  • Direct memory access with PEEK and POKE from the DOS command line
  • About 40 Basic commands are new or enhanced.

Contents

  Length      Date    Time    Name
---------  ---------- -----   ----
   261136  2009-03-21 15:23   NewDos86_90Hlp1.dmk
    25234  2009-03-21 15:51   NewDos86_90Hlp1.png
   261136  2009-03-21 15:23   NewDos86_90Hlp2.dmk
    24406  2009-03-21 15:54   NewDos86_90Hlp2.png
   261136  2009-03-21 15:24   NewDos86_90Hlp3.dmk
    27412  2009-03-21 15:55   NewDos86_90Hlp3.png
   261136  2009-03-21 15:17   NewDos86_90M1.dmk
    26366  2009-03-21 15:46   NewDos86_90M1.png
   261136  2009-03-21 15:18   NewDos86_90M3.dmk
   261136  2009-03-21 15:20   NewDos86_90M3HD.dmk
    26584  2009-03-21 15:43   NewDos86_90M3HD.png
    24671  2009-03-21 15:47   NewDos86_90M3.png
   261136  2009-03-21 15:25   NewDos86_90Type_cmd.dmk
    22884  2009-03-21 15:55   NewDos86_90Type_cmd.png
   261136  2009-03-21 15:21   NewDos86_90Util1.dmk
    24309  2009-03-21 15:45   NewDos86_90Util1.png
   261136  2009-03-21 15:16   NewDos86_90Util2.dmk
    27324  2009-03-21 15:48   NewDos86_90Util2.png
   261136  2009-03-21 15:22   NewDos90PDUpdPD1.dmk
    19089  2009-03-21 15:53   NewDos90PDUpdPD1.png

NewDos86_90.zip

NewDOS Plus
Version 2.1 - Version 3.0
by Apparat, Inc.

Model RAM Size
Model 1 16k - 48k 88k

Backing Up NewDOS Plus

NewDOS+ doesn't have a BACKUP command but instead uses the COPY command to make an image backup. Thanks to the information I received from "Skipp May" I was able to determine the format of the COPY command, it is:

COPY :X TO :Y 00/00/00

Double-Zap/II

Double-Zap/II is a double density modification for NEWDOS 2.1+. Distributed by OMNICOMP, it enables NEWDOS+ to use a Percom double density controller.

Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
24.09.00 16:32       13912    130576   10%  DBLZAP.DSK                    
30.10.99 19:36       53304    114256   46%  NEWDOS30.DSK                  
03.05.01 14:25       21764    114256   19%  NEWDOS21.DSK                  

96-0006.ace / 96-0006.zip

RapiDOS
Version 2.0
by Rapidynamic Software, Inc.

Model RAM Size
Model 4 64k - 128k 22k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
22.09.00 14:49       21540    256016    8%  rapidos.dsk 

96-0002.ace / 96-0002.zip

TRSDOS (Model 1)
Version 2.1 & Version 2.3
RS Catalog # 26-2104 / Copyright 1978-1979

Model RAM Size
Model 1 16k - 48k 39k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
31.07.99 13:16       36596    114256   32%  TRSDOS23.DSK                  
31.07.99 13:39        2840    114256    2%  TRSDOS21.DSK

26-2104.ace (corrupted)

TRSDOS (Model 1)

RS Catalog # 26-2208 / Copyright 1979

Model RAM Size
Model 1 16k - 48k 39k
Contents

  Length      Date    Time    Name
---------  ---------- -----   ----
   261136  2012-01-13 13:12   TRSDOS23B.DMK

26-2208.zip

TRSDOS (Model 1)
Version 2.7DD
RS Catalog # 26-1143 / Copyright 1981

Model RAM Size
Model 1 16k - 48k 45k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
12.05.00 15:29       44880    224016   20%  trs27r.dsk                    
28.07.99 22:19         412    224016    0%  trs27p.dsk

26-1143.ace / 26-1143.zip

TRSDOS (Model 3)
Version 1.3
RS Catalog # 26-2111 / Copyright 1980

Model RAM Size
Model III/4 16k - 48k 35k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
05.04.99 14:03       34796    256016   13%  TRSDOS13.DSK

26-2111.ace / 26-2111.zip

TRSDOS (Model 4/4P)
Version 6.2
RS Catalog # 26-0316 / Copyright 1984

Model RAM Size
Model 4 64k - 128k 143k

SIX2XTND(C) Version 1.2.2 06/06/87 - PATCH FOR TRSDOS 6.2.x Model 4

This software consisting of a set of patches and a conversion program will enable you to continue to use your TRSDOS 6.2.x operating system past 1987 to the year 2092. The USER password has been eliminated, but all other passwords remain.

These patches are on a TRSDOS 6.2x data virtual floppy (.DSK). Read the docs in the .ZIP and on the .DSK for more info on what the patches do and how to apply them. I applied this patch to both my TRSDOS 6.20 and 6.21 operating systems without problems (read the instructions carefully).

Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
28.05.99 12:43        3588      8933   40%  SIX2XTND.DOC
28.05.99 11:20       11844    256016    4%  SIX2XTND.DSK
02.05.01 13:10       90908    256016   35%  TRS4HARD.DSK                  
01.04.99 16:10       35036    512016    6%  TRS620.DSK                    
25.03.99 19:22        3972    256016    1%  TRS621.DSK 

26-0316.ace / 26-0316.zip

UltraDOS
Version 4.2
by Percom Data

Model RAM Size
Model 1 16k - 48k 45k

Backing Up UltraDOS

UltraDos doesn't have a BACKUP command but instead uses the COPY command to make an image backup. Thanks to the information I received from "Skipp May" I was able to determine the format of the COPY command, it is:

COPY :X TO :Y 00/00/00

Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
30.10.99 19:09       65632    205648   31%  ULTDOS42.DSK                  

96-0008.ace / 96-0008.zip

VTOS
Version 3.0
by Virtual Technology

Model RAM Size
Model 1 16k - 48k 39k
Contents

  Date    Time     Packed      Size  Ratio  File                          
                                                                          
12.08.99 02:56       38844    114256   34%  VTOS30.DSK                    

96-0009.ace / 96-0009.zip

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