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Definitive List of Model II Operating Systems

pski

pski

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Continuing with the Model II lovefest and intrigued by other discussions on Model II operating systems, I decided to see if I can compile a definitive list of Model II operating systems. Please add your wisdom, comments, links to resources and corrections and lets see if we can create a reference-able resource together. I will update the main post as needed.


Model II Operating Systems (in chronological order)

TRSDOS Model II Version 1.1/1.2

The original Model II Z80 operating system which was released with the first Model II in 1978. Supports SSDD 8” floppy drives only. Was replaced by 2.0 fairly quickly.

TRSDOS 2.0

The second OS release for the Model II probably circa 1979. Many bug fixes and enhancements over TRSDOS 1.1/1.2 but they are completely incompatible formats. Referred to as 2.0a once 2.0b became available.

TRS-80 Model II Disk Operating System Reference Manual

TRSDOS 2.0b

Released with the Model 16 in 1982 with support for the Thinline Tandon 848 drives. Otherwise the same as 2.0a.

TRSDOS 2.0d

This was an officially unreleased TRSDOS 2.0 version that supported both the SSDD Model II and the DSDD Thinline Model 12/16 drives.

TRSDOS HD

There are references to TRSDOS-HD in the Model 16 documentation set but I have never seen it and not sure if it ever was released. It may be a moniker for TRSDOS II 4.0.

TRSDOS II 4.0

Completely new third Model II OS with HD support. This release actually requires a hard drive adapter because the OS requires 64k + 16K (found on the HDA). The hard drive needed to be initialized with the Hard Disk Initialization System which ran under TRSDOS 2.0.

TRSDOS-II Reference Manual

TRSDOS II 4.1

Introduced with the Model 16. Added support to bootstrap the new TRSDOS-16. OS could now use 16k from the 68000 memory on a Model 16 so it did not require a HDA on these machines.

TRSDOS-16

First 16 bit operating system released for the Model 16. Uses TRSDOS II 4.1 as a boot loader. Makes extensive use of TRSDOS || 4.1 under the covers. The most hybrid and hence most complicated and hence most problematic Tandy OS released.

TRSDOS-16 Disk Operating System

TRSDOS II 4.2

Introduced with the Model 12. The OS could now also use the additional 16K from the B design machine's motherboard so it did not require a HDA on these machines. There were many iterations of 4.2.x which supported different combinations of HD adapters and controllers.

TRSDOS II 4.3

Added Arcnet support.

TRS-XENIX 1.x

Released for the Model 16 after Tandy realized TRSDOS-16 was a flop. Licensed from Microsoft.

TRS-Xenix Operations Guide

TRS-XENIX 3.x

Released for the Model 6000. Requires the 8Mhz 68000 CPU board found in the 6000. The 6Mhz board in the 16B can be upgraded to 8Mhz according to Tech Bulletin 12/16B:044.


CP/M

Lifeboat CP/M

P&T CP/M 2.2

P&T CP/M 2 User's Manual

Aton CP/M

CP/M-68K

A 68000 version of CP/M that runs on the 68K subsystem in the TRS-80 that requires any one of the z80 CP/M 2 operating systems to be installed. It is similar to TRSDOS-16 in that it uses the underlying 8-bit operating system as a boot loader and I/O system. A very interesting feature is that you can switch between z80 CPM and 68k CPM and back without losing the 68k context.

TriSoft CP/M-68K TRS-80 User's Guide

CP/M Plus

Tandy badged version of CP/M 3 from DRI. It supported bank switching on the Model 12/16B/6000 so could utilize 128K of z80 memory if the machine was upgraded appropriately. See Tech Bulletin 12/16B:18.

Non-Tandy Other

LS-DOS 6.3.1A

Compatible with the Model 4 version of LS-DOS 6.3.1. Can also utilize the optional additional z80 64K on the main logic board on the 12/16B/6000. See details below. Can be downloaded here.

DOSPLUS II
 
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Chromedome45 said:
missed DOSPLUS although I have not seen DOSPLUS in the wild.
Click to expand...

The vc.net archive has some DOSPLUS images for Model II. I will add DOSPLUS to the list.

Here's an ad for DosPlus II I just came across

Screen Shot 2015-07-07 at 9.58.02 PM.jpg
 
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Lifeboat CP/M

Xenix 3.x requires an updated PAL in U34 for release 2 68000 boards. Checksum for that PAL ends in D4. It will not work on the Rev 1 68000 boards (the dog eared version). Rev 3 boards have upgraded PAL and run at 8MHz natively.
 
I would like to get documentation of the filesystem formats of as many of these as possible. I'm working on a Python package + utilities for manipulating ImageDisk (.IMD) files, and I plan to add support for getting directory listings, adding files, extracting files, and initializing images of blank formatted media for some of the operating systems which interest me. I doubt that I'll cover the majority of systems for which there are .IMD images on Dave's ImageDisk site, but I'd like to support the more common TRS-80 operating systems.

The code I have up on GitHub at the moment is still "version 0.0.0 ALPHA", but I think it's at a point where it's already useful for getting a bit of information out of .IMD files such as low-level format type, changing sector interleave and skew, and writing Python programs that can fiddle with .IMD files. It's pretty lacking in the documentation department, though.
 
Pete, there was an LS-DOS 6.2 for Model II, made by LSI before the 6.3.1A was done by Misosys. I have a copy of the disk for that release.

Compatibility between LS-DOS 6.3.1 on model 4 and on the II-series is actually pretty good, and it is documented in the README/DOC found on the disk. Also note that the very first thing you should do after booting is run mod12/jcl if you're on a Model 12-chassis (12/16B/6000) or a 16, with thinline drives. The README/DOC from my LS-DOS disk is attached.
 

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I found some TD0 files for what may actually be Lifeboat CP/M, P&T CP/M, CP/M Plus and CP/M 68K in the Maslin archives. Has anyone here ever tried to create disks from these images? Although I am working on it, I don't have a rig set up yet to run ImageDisk which is supposed to be able to convert TD0 to IMD files.
 
Thanks for linking to the Maslin Archives. I've downloaded them for "when I get around to it". :)

I've used ImageDisk a bit, but I don't have my ImageDisk PC set up at the moment. I'll try converting some TD0 files next time I set it up.
 
Although I have been able to make imagedisk run it seems picky about the hardware and OS. The only way I can even get it to run is on a win 95 machine and then only by choosing safe mode command prompt where no drivers get loaded. Go figure. Teledisk is much more forgiving IMHO. So I run teledisk to convert .TD0 images.
 
I just picked up a dual boot Win95/MS-DOS machine so it sounds ideal for ImageDisk. I never thought I'd be working with MS-DOS again!
 
Chromedome45 said:
So with my 68000 board dead how can I run TRSDOS II 4.2 now? I was told not to add the 16k RAM on the 6000. Wonder why
Click to expand...

You have the HDA which has the 16k on it so you should be ok.

So are you suspecting that adding the 16k to your mainboard fried your 68k CPU?
 
No I think I may have knocked it out some way. When I was reheating some pins I accidently created a bridge between a pin on the PROM at U45 and a via. when that bridge was there it was preventing the 6000 from booting up properly. That may have put some excess current on that pin and knocked out the PROM.
I discovered the short and removed it. After that I think the 68K board responded properly a couple of times then now nothing. So I may have killed it!
Would need to get a replacement PROM to be sure. And that may be nearly impossible to find unless someone has a good 8 MHz 68k board and a PROM programmer. Then could maybe read the prom and copy to a new PROM. But that may not even be possible.
 
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Pete I did find a different version of LifeBoat CP/M it is the maslin archives filename is trsiilbt.td0 It is in the 1997 folder. looks like an original disk

My imagedisk/teledisk/trs80 emulator system is a Pentium 233 2 GB HD 128 MB ram It has windows 95 but I don't use it to often. It has a Adpatec 1522
ISA SCSI controller card in it. Why? the floppy controller on it will handle Single density disks.

Never forget the command prompt! It can do some things windows utilities can't. Example create a partition on a brand new drive, Can't do it under windows 7
disk manager you have to go to the command prompt and run diskpart! go figure
 
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U50 information removed.....

EDIT: ah, I see you've edited the post to read U45, the 82S153 PLA (data sheet actually calls it a Field programmable logic array, but it's one-time programmable). Its equations are on page 91 of the PDF, page 87 of the hardcopy. This should not be difficult to make from a modern GAL, for someone with the time, a programmer, and a stock of compatible GALs. It also shouldn't be too difficult to test, with the equations defined in the service manual, just need a fairly simple logic test breadboard.
 
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Yeah U50 is the 3482 Latch. Strange thing is if you at NF6X 68K CPU board his has a 74AS533 in that position. So just for grins I put one of those in mine. Acted the same of course.
 
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