TRS-80 News

May 20, 2026 - Model I Disassembly Page Drastically Rewritten

When I was updating the Model III page based on the original source code, correcting a whole lot of errors in the process, I realized that the Model I page, which was the first diassembly done, had a LOT of flaws: Typos, bad jumps, etc.

What I decided to do was to take all the work I had just done on the Model III and back port it to the Model I page, but to include the original labels, the original 8080 source code and comments by Gates/Allen, and options to use labels or hex.

So the new page will generate based on the 5 different Model I ROM versions, and then you can choose whether your want Hex or Labels (or both), the Z-80 Opcodes, the 8080 Opcodes, and you can customize up to 5 different types of commentary.

The result is a web page which is built on the fly based on user preference through check boxes - albeit a 3MB page, so a touch of patience is required for your browser to build the page per your specifications.

The new page is here

The old pages are still present, but not linked - they can be found here

May 12, 2026 - TRS80Tools Updated to v2.8.9

Lawrence Kesteloot has released an updated copy of his trs80tools, now new version 2.8.9. Updates are to the DISASM command as follows:

  • No longer automatically specifies Model III ROM entry points when disassembling a ROM since the ROM might not be for a Model III.
  • When specifying the --no-labels flag, jumps to the current address will list the address and not the $ symbol.
  • Data now uses DEFB instead of .BYTE.
  • Disassembly warnings are now sent to standard error instead of standard out.

You can download it for the Windows, Mac, and Linux at https://www.my-trs-80.com/tool/#installation.

May 19, 2026 - SDLTRS2 Updated to v1.2.35

Thanks to David S, I am told that Jens Guenther has updated his Windows/Linux fork of the SDLTRS Emulator to v1.2.35

Changelog:

  • Added memory size selection for TRS-80 Model I/III.
  • Added CPU clock rate option for selected TRS-80 Model.
  • Fixed TRS-80 Model 4/4P character display.
  • Fixed bugs and internal improvements.

You check it all out at https://gitlab.com/jengun/sdltrs/-/releases

May 10, 2026 - Model III ROM Dissassembly and Addresses

I have finished two new pages dealing with the Model III Addresses/Official Labels:

Each of those pages includes a breakdown as to what the address actually does. In the case of ROM addresses, what jumping to it does, and in the case of RAM Addresses, what ROM addresses use it and why.

These projects also allowed me to make adjustments and fixes to the Model III ROM Disassembled pages both in terms of small errors and by adding some checkboxes to streamline viewing.

May 8, 2026 - New Tandy Publications

Diane Kester has provided a the Student Manuals! Thank you, Diane!

Title:Student Manual Part 1 Introduction to BASICPublisher:Radio ShackYear:1980Size:53,865,313Pages:88OCRed:Yes*Notes:26-2151

Title:Student Manual Part 2 BASIC ProgrammingPublisher:Radio ShackYear:1980Size:60,725,552Pages:118OCRed:Yes*Notes:26-2153 / Appendix A Missing

May 7, 2026 - TRS-80 Trash Talk Live # 49

The next TRS-80 Trash Talk live show is Saturday, May 23, at 6:00PM Pacific Daylight Time / 9:00PM Eastern Daylight Time!

You can watch on the TRS-80 Trash Talk channel: https://www.youtube.com/channel/UCXkGugvdCkpkMDylVQb9gfg

If you want to participate in the live zoom session, reach out to trs80trashtalk at gmail dot com for information.

May 7, 2026 - Macrotronics M80 Hardware Manual

Pascal Holdry has provided the manual for the Macrotronics M80 Ham Interface! Thank you, Pascal!

Title:M80 Ham InterfacePublisher:Ronald Lodewyck - MacrotronicsYear:1979Size:5,945,693Pages:60OCRed:YesNotes:With Technical Bulletin 1

May 7, 2026 - Site Update

A page discussing MicroDOS has been added. The page includes some historical background, an online manual, and a disassembly of the "DOS" portion.

May 5, 2026 - VTOS Manuals from Tim Mann

Tim Mann has provided a bunch of VTOS manuals! Thank you, Tim!

Title:VTOS v3.0Publisher:Randolph Cook-Virtual TechnologyYear:1979Size:11,571,760Pages:36OCRed:YesNotes:Set 2

Title:VTOS v3.0 Update LetterPublisher:Randolph Cook-Virtual TechnologyYear:1979Size:404,621Pages:1OCRed:Yes

Title:VTOS v4.0Publisher:Randolph Cook-Virtual TechnologyYear:1979Size:9,555,970Pages:48OCRed:Yes

Title:VTOS v4.0 AddendumPublisher:Randy CookYear:19xxSize:1,753,666Pages:4OCRed:Yes

Title:VTOS v4.0.1Publisher:Quality Software DistributorsYear:1980Size:5,259,174Pages:20OCRed:Yes

Title:VTOS v4.0.2Publisher:Quality Software DistributorsYear:19xxSize:12,385,710Pages:26OCRed:Yes

May 4, 2026 - New Publications from John Gruver

John Gruver has provided some additional publications! Thank you, John!

Catalogs

Title:Electronic Systems CatalogPublisher:Electronic SystemsYear:1978Size:7,526,171Pages:20OCRed:Yes

Title:Misosys Catalog xx-xxPublisher:MisosysYear:19xxSize:2,879,379Pages:16OCRed:Yes

Title:Radio Shack Games Pack I FlyerPublisher:Radio ShackYear:19xxSize:3,680,688Pages:1OCRed:YesNotes:26-1805

Title:Radio Shack TRS-80 Service Contract Interest CardPublisher:Radio ShackYear:19xxSize:448,370Pages:2OCRed:YesNotes:Set 2

Hardware Manuals

Title:CTR-80 Cassette Tape Recorder Owners ManualPublisher:TandyYear:19xxSize:2,663,892Pages:2OCRed:YesNotes:26-1205 / Set 3

Title:Important Information for Cassette Users Level IIPublisher:TandyYear:19xxSize:826,216Pages:2OCRed:YesNotes:Set 2

Title:Important Information for Cassette Users Model IIIPublisher:TandyYear:19xxSize:2,025,180Pages:4OCRed:YesNotes:Set 3

Title:Information Guide for New Computer OwnersPublisher:TandyYear:19xxSize:3,883,151Pages:12OCRed:YesNotes:Set 3

Title:Model 4D Disk System Owners Manual AddendumPublisher:TandyYear:1983Size:1,361,049Pages:5OCRed:YesNotes:875-9732

Title:Model 4D Disk System Owners Manual AddendumPublisher:TandyYear:1983Size:1,555,850Pages:6OCRed:YesNotes:875-9742

Title:Model III Disk System Owners Manual Supplement for 26-1065Publisher:TandyYear:19xxSize:623,922Pages:2OCRed:Yes

Title:Model III Disk System Owners Manual Supplement for TRSDOS v1.3Publisher:TandyYear:19xxSize:1,300,500Pages:1OCRed:YesNotes:XFERSYS

Title:Mostek Z80 Microcomputer Micro-Reference ManualPublisher:Mostek CorporationYear:1978Size:3,098,510Pages:18OCRed:YesNotes:Set 2

Title:Percom Doubler Users ManualPublisher:Percom Data CompanyYear:1980Size:43,961,201Pages:46OCRed:YesNotes:Set 2

Title:PS-401 SchematicPublisher:Percom Data CompanyYear:19xxSize:151,120Pages:1OCRed:Yes

Title:Teac FD-55ABEFG Drive SpecificationPublisher:Teac Corporation of AmericaYear:19xxSize:10,345,120Pages:44OCRed:Yes

Service Manuals

Title:Model 4 and 4P Technical Reference ManualPublisher:Tandy CorporationYear:1985Size:98,460,368Pages:526OCRed:YesNotes:Set 3 / 526 Pages

Title:SA400 Floppy Disk Drive Service ManualPublisher:Shugart AssociatesYear:1977Size:17,965,636Pages:64OCRed:Yes

Software Manuals

Title:Accounts PayablePublisher:TandyYear:1983Size:106,122,119Pages:208OCRed:YesNotes:26-1554

Title:AIDSPLUS-II with AutoKey v1.0Publisher:SofTrendsYear:1985Size:88,269,253Pages:176OCRed:YesNotes:Set 3

Title:DeskMate v1.0 Reference Manual AddendumPublisher:TandyYear:19xxSize:23,140Pages:1OCRed:YesNotes:875-9764

Title:DeskMate v1.0 Reference Manual AddendumPublisher:TandyYear:19xxSize:333,107Pages:1OCRed:YesNotes:875-9770

Title:DeskMate v1.0 Reference Manual AddendumPublisher:TandyYear:19xxSize:365,185Pages:1OCRed:YesNotes:875-9771

Title:DeskMate v1.0 Reference Manual AddendumPublisher:TandyYear:19xxSize:110,007Pages:1OCRed:YesNotes:875-9782

Title:DIRCAT v1.0 (1984)([SofTrends][OCR]Publisher:Unknown PublisherYear:19xxSize:8,214,056Pages:32OCRed:YesNotes:SofTrends

Title:Golden Oldies System Enhancement PackagePublisher:MisosysYear:1988Size:47,267,109Pages:82OCRed:YesNotes:Set 1 / PDF

Title:LS-DOS 6.3 Update For TRSDOS 6.2.XPublisher:Logical SystemsYear:19xxSize:15,778,554Pages:47OCRed:Yes

Title:LS-DOS Update From 6.3.0 to 6.3.1Publisher:Misosys IncYear:1990Size:1,489,315Pages:4OCRed:Yes

Title:MMSForth v1.9 Quick Reference CardPublisher:Miller Microcomputer ServicesYear:1982Size:1,139,915Pages:2OCRed:Yes

Title:VTOS v3.0Publisher:Randolph Cook-Virtual TechnologyYear:1979Size:9,863,376Pages:16OCRed:YesNotes:Set 1

Tandy Memos

Title:Computer Services MemoPublisher:Radio ShackYear:1979Size:524,237Pages:1OCRed:YesNotes:TRSDOS Version 2.2

Title:Computer Services MemoPublisher:Radio ShackYear:1979Size:569,896Pages:1OCRed:YesNotes:TRSDOS Version 2.3 New Release

Title:Fact SheetPublisher:Radio ShackYear:1979Size:8,612,726Pages:22OCRed:YesNotes:TRSDOS v2.2

May 3, 2026 - Labels in Model III Disassembly - Part 2

For those who might have a need or want, a new page devoted the Model III ROM Labels has been added. Thanks to the magic of Gemini, the page offers 4 different formats.

The labels used are exclusively the ones used in the original Model I PDP-10 source code by Gates and Allen, augmented Frank Durda's labels for parts that were involved in the conversion of routines to the Model III.

May 2, 2026 - Labels in Model III Disassembly

Largely because the TRSDOS v1.3 BASIC project left me with a lot of labels which were missing, I have now gone through the Model III ROM Disassembly and have redone all of the labels.

I started with the original PDP-10 source code for the Model I written by Gates/Allen and tracked down the corresponding Z-80 code, using their labels.

Then, for code which was changed from the Model I to be Model III, I used Frank Durda's source code to track down those remaining labels. Thankfully, for the overwhelming majority, Frank decided to keep those labels.

May 1, 2026 - New TRS-80 Game - BEAST

Voidstar has release a new game for the TRS-80 Model I and III called BEAST. He writes about its origin:

This was kind of an accidental project. I never messed with 2x3 semigraphics, and I wanted to demo about it using the POLY-88 (since it's that systems 50th anniversary this year) at VCF next month. Well, its VTI video card is having some issues now. So - I figured how hard could it be to port the 8080 code and 2x3 semigraphics over to the Z80 and the TRS-80's 2x3 semigraphics? Well, it was an adventure - the POLY-88 at least has a 60Hz timer for RNG and tempo-timing. I aimed to support a TRS-80 M1 without an Expansion Unit (since that's all I have in real hardware). But thanks to help with some folks, I went ahead and made the binary/CAS/WAV/CMD compatible with both the M1 and M3 (sorry M2's and M4's!). I do this by probing for the M3's timer clock first. Anyway, it matches the POLY-88 version. There is a README TEXT (and source) in the ZIP for more instructions.

You can watch the game play at https://www.youtube.com/watch?v=k7GsxYuFI3o

The GITHUB is at https://github.com/voidstar78/BEAST/tree/main/TRS80_VERSION

April 27, 2026 - Site Updates

  • Thanks to a program writing by Gemini, I have gotten JSON OCR from Mistral for all 7,963 zips in the 'publications' folder, although a few PDF's had to be regenerated. I have looked at the output, and it is by no means perfect, but it is orders of magnitude better than what was there from either AABBYY Finereader or Adobe Acrobat Pro.
    UPDATE: At this point, I have re-uploaded all downloadable PDF's and every one of them should have the .json and sidecar.txt in it. I am, however, starting the "Phase 2" of creating PDF's with the Mistral OCR replacing the existing OCR, and the files will be re-uploaded once that occurs.
  • A site visitor Airton was kind enough to point out that there are discrepancies between the Level 1 source in github, his work on the Level 1 source, and the Level 1 disassembled page here.
    UPDATE:The page has now been corrected.
  • Downloads for Level 1 programs have been fixed, thanks to Quentin pointing out that they were not functioning.
  • The TRSDOS v1.3 disassembly re-do project is winding down. All 15 SYS files have been reprocessed against Frank Durda's source file. I plan on doing BASIC/CMD as well to finish up the set once the credits refresh. I also realized that XFERSYS was never disassembled, so that will be on the to-do list as well. I wish all the background information and files required to do these didn't use up so many credits.

April 25, 2026 - Site Updates

The first, which I am 2/3 of the way through, is updating the TRSDOS v1.3 disassembly pages to merge in the official Frank Durda source code labels and comments. This is tough going because of misformed pages to begin with. It also uses a ton of credits because I have to feed in a disassembly, the HTML (which is about 500MB each), and all of Frank's source and dependencies.

The second, is to re-OCR the documents. There are currently 7,963 zips in the 'publications' folder. The process uses cURL to upload the PDF to the Mistral API and retrieve a unique file ID, which is then passed to a PowerShell script to trigger the OCR model and generate a text sidecar, which is then used by OCRmyPDF to inject a searchable text layer back into the original document. During this final assembly, Tesseract performs a local OCR pass to handle any missed coordinates and refine text placement, while Ghostscript acts as the rendering engine to optimize the PDF's internal structure and compress the file for archival storage. Mistral is utilized because it employs the new Vision-Language Model (VLM) that is better than the basic pattern-matching of legacy tools by using deep contextual understanding to accurately "read" and reconstruct text even through the heavy noise, dot-matrix distortion, and ink-bleed common older publications. It is possible that the JSON can be used for indexing the archive's full-text search engine or programmatically extracting metadata from the magazines.

April 24, 2026 - New TRS-80 Game

Nickmann Studios has developed a new game for the TRS-80 - "House on the Edge of the Crater"

The authorities of the age of normality have exiled the most creative people to the moon: artists, scientists, dangerous eccentrics, and keepers of great secrets.
You are Yordi, the reporter.
Conduct interviews with the residents, explore the house on the edge of the crater and bring back to earth the knowledge that could transform the cold world of the age of normality.
Based on the novel house on the edge of the crater by István Nemere and Gábor Képes.
Requirements for a successful mission: Conduct 9 interviews and obtain all 3 keys.

It is a 'name your price' download - You can find all the information and download links at https://nickmann-studio.itch.io/crater

April 20, 2026 - VTOS Update

Tim Mann has gone through all known copies of VTOS on DMK and has prepared a complete set of Duplicator/Master/System/Data disks for what he could determine is the purest/best copy archived:

  • VTOS v3.0.0 Set - Duplicator/Master/System/Data - Created by Tim Mann
  • VTOS v3.0.1 Set - Duplicator/Master/System/Data - Created by Tim Mann

April 12, 2026 - New Publications

John Gruver has provided some additional publications! Thank you, John!

Software

Title:Aerocomp Hard Disk Driver Boot Disk Creation InstructionsPublisher:AerocompYear:19xxSize:3,104,961Pages:2OCRed:Yes

Title:AIDSPLUS-II with AutoKey v1.0Publisher:SofTrendsYear:1985Size:340,738,561Pages:228OCRed:YesNotes:Set 2

Title:ARC31 v2.00Publisher:David Huelsmann-SEAYear:1987Size:1,713,005Pages:19OCRed:Yes

Title:Auto-Mate v1.0Publisher:SofTrendsYear:1986Size:1,153,043Pages:22OCRed:Yes

Title:Back-Rest Fast Hard Disk BackupPublisher:Breeze Computing-QSDYear:1983Size:4,523,689Pages:8OCRed:YesNotes:RS90-0244

Title:BeepPublisher:Logical Systems IncYear:19xxSize:2,674,383Pages:2OCRed:Yes

Title:BSORT and MOD324Publisher:MisosysYear:1984Size:11,562,553Pages:10OCRed:YesNotes:Set 2

Title:ConvCPM v2.0Publisher:Rich N Deglin-Roy SoltoffYear:1983Size:13,565,366Pages:16OCRed:Yes

Title:DescribePublisher:MisosysYear:1984Size:7,027,896Pages:6OCRed:Yes

Title:DiskMod EDTASMPublisher:MisosysYear:19xxSize:19,694,880Pages:16OCRed:Yes

Title:DISnDATa v1.0Publisher:C W Medlock - Pro-AM SoftwareYear:1982Size:4,154,090Pages:8OCRed:Yes

Title:FileAid for AIDS Plus-IIPublisher:SofTrendsYear:1985Size:11,001,184Pages:32OCRed:Yes

Title:FM File ManagerPublisher:Logical Systems IncYear:1983Size:44,313,467Pages:36OCRed:YesNotes:MiL-30-051

Title:Formation Forms Management SystemPublisher:Software Concepts-TandyYear:1983Size:174,992,121Pages:261OCRed:YesNotes:26-1527 / Set 2

Title:Hard Disk BackupPublisher:Montezuma MicroYear:1986Size:12,417,782Pages:13OCRed:Yes

Title:Home AccountantPublisher:Continental Software-Radio ShackYear:1983Size:37,094,721Pages:174OCRed:YesNotes:RS26-1511

Title:Le Script v1.2 Manual CPublisher:Anitek Software ProductsYear:1983Size:81,225,588Pages:96OCRed:Yes

Title:Little Brother 86 Installation Manual for MSDOSPublisher:MisosysYear:1991Size:126,635,185Pages:216OCRed:YesNotes:M86-510

Title:Little Brother Database Manager Installation Manual for LDOSPublisher:MisosysYear:1987Size:2,725,048Pages:12OCRed:YesNotes:Set 2

Title:Little Brother Database Manager Installation Manual for Model 4Publisher:MisosysYear:1991Size:3,233,187Pages:12OCRed:YesNotes:Set 3

Title:Little Brother Database Manager Supplemental DocumentationPublisher:Logical SystemsYear:1985Size:21,219,777Pages:32OCRed:Yes

Title:LS CompPublisher:Logical Systems IncYear:1983Size:1,788,603Pages:2OCRed:YesNotes:MiL-32-010

Title:LSI Help SystemPublisher:Logical Systems IncYear:1984Size:22,675,907Pages:22OCRed:YesNotes:MiL-30-060

Title:LS QFBPublisher:Logical Systems IncYear:1984Size:2,536,515Pages:2OCRed:YesNotes:M4 / MiL-32-010

Title:LU4 Library Utility v1.40Publisher:David HuelsmannYear:1986Size:7,727,568Pages:6OCRed:Yes

Title:LUM3 v1.23Publisher:David HuelsmannYear:1986Size:6,332,665Pages:5OCRed:Yes

Title:LUM4 v1.13Publisher:David HuelsmannYear:1986Size:6,332,665Pages:5OCRed:Yes

Title:LUMN3 v1.01Publisher:David HuelsmannYear:1986Size:6,332,669Pages:5OCRed:Yes

Title:Mach2Publisher:Karl A Hessinger-MicroConsultantsYear:1983Size:15,682,740Pages:14OCRed:Yes

Title:MARC4 v2.01Publisher:System Enhancement AssociatesYear:1987Size:11,046,710Pages:11OCRed:Yes

Title:Montes ToolkitPublisher:Montezuma MicroYear:1985Size:15,839,650Pages:12OCRed:Yes

Title:Montes WindowPublisher:Montezuma Micro-JBOYear:1984Size:26,643,579Pages:23OCRed:Yes

Title:Montezuma Micro 15MB Hard Disk SupportPublisher:Montezuma MicroYear:1984Size:33,650,299Pages:28OCRed:Yes

Title:Montezuma Micro CPM v2.2 Update to v2.3Publisher:Montezuma MicroYear:1986Size:1,453,818Pages:1OCRed:Yes

Title:Montezuma Micro Public Domain DisksPublisher:Montezuma MicroYear:19xxSize:2,076,518Pages:1OCRed:Yes

Title:M-ZAL CompilerPublisher:Jeff Krantz and David Willen-Computer Applications UnlimitedYear:1981Size:88,883,706Pages:106OCRed:YesNotes:Set 2

Title:NEWDOS-80 v2.0 for Model IPublisher:Apparat IncYear:1981Size:290,657,673Pages:292OCRed:YesNotes:Set 3 / Serial 025845

Title:NSweepPublisher:Dave RandYear:1984Size:16,322,725Pages:16OCRed:Yes

Title:Nulu v1.1Publisher:Martin MurrayYear:1985Size:23,533,879Pages:22OCRed:Yes

Title:OverDrivePublisher:Logical Systems IncYear:1984Size:4,723,518Pages:4OCRed:YesNotes:LSL35-220

Title:Pro-ESPPublisher:Richard Deglin-MisosysYear:1984Size:26,504,902Pages:26OCRed:Yes

Title:PRO-ZGraphPublisher:Karl Hessinger-MisosysYear:1983Size:24,634,971Pages:24OCRed:Yes

Title:Re-VisePublisher:SofTrendsYear:1986Size:28,846,917Pages:22OCRed:Yes

Title:SQ3 Squeeze v1.01Publisher:David HuelsmannYear:1985Size:10,720,083Pages:10OCRed:Yes

Title:SQ4 v1.01Publisher:David HuelsmannYear:1985Size:10,720,083Pages:10OCRed:Yes

Title:Sweep4 v1.00.00Publisher:Kachina Software GroupYear:1992Size:8,185,625Pages:9OCRed:Yes

Title:TBUG Z-80 Monitor and Debugging AidPublisher:Radio ShackYear:1978Size:489,788Pages:12OCRed:YesNotes:26-2001 / Set 2

Title:Toolbelt for TRSDOS 6.xPublisher:Breeze-QSDYear:1983Size:47,332,125Pages:44OCRed:YesNotes:Set 2

Title:USQ3 v1.01Publisher:David HuelsmannYear:1985Size:10,720,083Pages:10OCRed:Yes

Title:USQ4 v1.01Publisher:David HuelsmannYear:1985Size:10,724,784Pages:10OCRed:Yes

Title:XARC4Publisher:David Huelsmann-SEAYear:1987Size:13,044,092Pages:13OCRed:Yes

Title:X-FTS File Transmission SystemPublisher:Rick C Francis-MisosysYear:1984Size:8,768,443Pages:8OCRed:Yes

Title:XPort File Transport Utility v1.0Publisher:SofTrendsYear:1986Size:31,460,153Pages:24OCRed:Yes

Title:XT-4 v1.6.8Publisher:Bill AndrussYear:1986Size:13,460,019Pages:10OCRed:Yes

Flyers

Title:8100 S-100 Bus AdapterPublisher:HUH ElectronicsYear:1978Size:1,314,739Pages:2OCRed:Yes

Title:VS-100 for the Model 4Publisher:Alpha ProductsYear:19xxSize:217,927Pages:1OCRed:Yes

Radio Shack Memos

Title:Radio Shack Memo - Printer Port Connections MemoPublisher:Radio ShackYear:1978Size:3,090,572Pages:4OCRed:Yes

Hardware Guides

Title:Parts Required to Add Disk Drives to TRS-80Publisher:PercomYear:19xxSize:3,272,059Pages:3OCRed:Yes

Title:RAM Upgrade InstructionsPublisher:Author UnknownYear:1985Size:2,973,772Pages:2OCRed:Yes

Title:TRS-80 Serial I-O Preliminary DocumentationPublisher:Electronic SystemsYear:1978Size:5,302,841Pages:5OCRed:Yes

Title:Your Hard Disk Drive and YouPublisher:Montezuma MicroYear:19xxSize:3,148,860Pages:2OCRed:Yes

April 11, 2026 - VTOS Update

Tim Mann is still at it on his VTOS work. A lot of online documentation (and the source material it is based on) had talked about Tim Mann figuring out, back in the day, how to create a "Duplicator Disk", which just sat and polled floppy drives and made a "Master Disk" (the one which was sold to the public) whenever it found a diskette. None of those sources ever documented how. Tim has now re-figured that out, and kindly provided one based on the original image. A link to that has been added to the VTOS page. He also noted that the VTOS v3.0.1 image zip file, which contained 5 different VTOS v3.0.1 DMK's, had two which were badly hacked. Those two have been removed and the zip file updated. Thank you again, Tim, for not only your work here, but your work over the decades for the TRS-80!

April 10, 2026 - VTOS Page

With extraordinary help from Tim Mann, the VTOS page is now up. It details the OS including the types of disks and copy protection, as well as a disassembly of the SYS files. It can be found at https://www.trs-80.com/sub-reference-dos-vtos-main.htm.

April 7, 2026 - VTOS Continues

Although I keep hitting the CLAUDE.AI caps very quickly, I am trying to progress with the VTOS v4.0.2 disassembly. Their way-too-tight caps just make it slow going.

I want to give a special shout out to Tim Mann and to Lawyrence Kesteloot, both of whom have been extremely helpful in navigating SYS6/SYS. This system file is in an ISAM/PDS format,meaning that it is a bunch of overlapping routines all jammed into one file, and special code is used to point to a specific byte in the file and say 'start running here'. Traditional disassembly simply won't work.

Tim has been extremely helpful in explaining/helping with the ISAM/PDS structure and answering questions as they came up.

Lawrence updated his trs-80tool a few times to assist, most recently to allow for file extraction from disks and to understand the additional codes inside a PDS sys file to permit disassembly. Before he did this, I failed 4 times in trying to disassemble the file.

You can download Lawrence's updated trs-80tool at https://www.my-trs-80.com/tool/#installation. Changelog for the past few (related) updates is:

  • v2.8.8 - Added --system flag to the convert command to extract system files from floppies. Updated so that disasm command understands LDOS-style PDS files for SYS6.SYS and SYS7.SYS, disassembling each overlay separately.
  • v2.8.7 - Disassemble VTOS .SYS files better by handling the CMD block type 0x10 (yanked load block) like 0x01 (data).
  • v2.8.6 - Handle .SYS files that are raw dumps of floppy boot sectors. These work with the info, hexdump, and disasm commands.

Thank you very much, Tim and Larence.

March 31, 2026 - Frustrating Tech Roadblocks

  • Yesterday the Disk Request Form came under really heavy attack and I received hundreds and hundreds of fake forms. The interesting part was that the attackers had a slight misconfiguration, and they were bleeding code into the fields. So I provided Gemini with my html/cgi as well as all their code. Gemini was able to determine what software they were using and updated the cgi accordingly. At least it stopped until the next time.
  • Claude usage caps are infuriating. I am trying to go through VTOS very carefully and the low caps are making this take a very very long time.

March 26, 2026 - New Books and Manuals

The next (VERY EXPENSIVE TO SHIP) shipment from Cris Peters has arrived!

Title:Clefs Pour Le TRS-80 Modeles I et III Tome 1Publisher:Remy Pineau-PSIYear:1983Size:118,583,963Pages:194OCRed:YesNotes:French

Title:Clefs Pour Le TRS-80 Modeles I et III Tome 2Publisher:Remy Pineau-PSIYear:1983Size:225,825,286Pages:202OCRed:YesNotes:French

Title:Desktop Plan-80Publisher:Personal Software-Radio ShackYear:19xxSize:140,405,537Pages:188OCRed:YesNotes:26-1594

Title:TRS-80 Model III-4 Handleiding Betreffende de Werking en de BASIC-ProgrammeertaalPublisher:TandyYear:1980Size:277,213,729Pages:274OCRed:YesNotes:Dutch
261-1069
Marked Up

Title:Handleiding Voor Level 1Publisher:TandyYear:1977Size:163,868,075Pages:244OCRed:YesNotes:265-9402 / Dutch / 1st Ed 2nd Printing

Title:TRSDOS and DISK BASIC HandleidingPublisher:TandyYear:1980Size:121,842,375Pages:202OCRed:YesNotes:26-9407 / Dutch

Title:Handleiding voor BASIC Level IIPublisher:Radio ShackYear:1980Size:150,090,568Pages:127OCRed:YesNotes:26-9405 / Dutch

Title:DMP-110 Operations ManualPublisher:TandyYear:1983Size:119,400,635Pages:68OCRed:YesNotes:26-1271

Thank you, Cris!

March 26, 2026 - Technical Manual

Sean O'Neill has provided a scan! Thank you, Sean!

Title:TRS-80 Technical Manual TroubleshootingPublisher:Radio ShackYear:1978Size:19,622,423Pages:24OCRed:YesNotes:Proof Copy / Set 3

March 26, 2026 - CPPIP / NPPIP / FPPIP v1.10

Mark Casteleijn has written a utility for TRS-80 CP/M to make copying files between disk drives, RetroNET Internet Adapter, and the FreHD hard disk emulator

Examples of the command line are:

CommandFunction
CPPIP FILE.DAT B:Copy FILE.DAT to drive B:
CPPIP *.COM B3:Copy all .COM files to drive B:, user area 3
CPPIP FILE.DAT B: /VCopy with CRC verify
CPPIP FILE.DAT B: /MMove (copy then delete source file)
NPPIP FILE.DAT IA:/Z/BK/Copy FILE.DAT to RetroNET IA store
FPPIP SD:FILE.COM A:Copy from FreHD SD card to drive A:
CPPIP /HDisplay full help information

You can find the GIT at https://github.com/ontheslab/cppip/releases/tag/v1.10.

March 25, 2026 - New Software

Scott Toenniessen has provided some additional software! Thank you, Scott!

Title:3-D Tic-Tac-Toe Year: 1984 Model: III Publisher: Rapidynamic Software

Title:3-D Tic-Tac-Toe Year: 1984 Model: 4 Publisher: Rapidynamic Software

Title:AOS Utilities Disk 1 Year: 19xx Model: III Publisher: Advanced Operating Systems

Title:Disk Drive Analyzer Year: 19xx Model: III/4 Publisher: Radio Shack + Verbatim Catalog Number: RS26-0413

Title:Master Diskette Directory III v1.2 Year: 1980 Model: III Publisher: Micro Systems Software Inc

Title:SuperKeys Year: 19xx Model: III Author: Phillip Mork Publisher: Programmers Guild

Title:XLR8er Installation Utility Year: 1986 Model: CP/M Publisher: Hi-Tech Inc

Title:XLR8er Installation Utility Year: 1986 Model: III Publisher: Hi-Tech Inc

Title:XLR8er Installation Utility Year: 1986 Model: 4 Publisher: Hi-Tech Inc

March 25, 2024 - TRSDOS v2.3

I have redone the TRSDOS v2.3 DOS disassemblies now that so much other work had been done in the interim. I am also now using Lawrence Kesteloot's trs80-tool to handle my disassembly generation (previously I used David Goben's Model III Disassembler after using George/Peter Philip's TRLD to convert /SYS to /CMD).

March 24, 2024 - JPC Products TC-8 Tape System

Sean O'Neill has let me know that David Shadoff has created a GIT to provide information about the JPC Products TC-8 Tape System for the TRS-80 Model I.

The GIT includes the EPROM, a KiCAD schematic, the manual, and the software.

The GIT can be found at https://github.com/dshadoff/TRS-80_TC-8.

March 24, 2026 - New Manuals

Ian Mavric has provided some additional manuals! Thank you, Ian!

Title:Air Flight SimulationPublisher:Dwight W Meyer-Instant SoftwareYear:1978Size:4,603,622Pages:24OCRed:YesNotes:IS0017R

March 23, 2026 - New Software

Ian Mavric has provided some additional software! Thank you, Ian!

Title:Ball Turret Gunner Year: 1979 Model: I Publisher: Instant Software Catalog Number: IS0051R

Title:Checker King Year: 19xx Model: Level 1 Author: Michael Marks Publisher: Personal Software

Title:Checker King Year: 19xx Model: I Author: Michael Marks Publisher: Personal Software

Title:Land Adventure Year: 1979 Model: I Author: Scott Adams Publisher: Adventure International

Title:Pirate's Cove Adventure Year: 1979 Model: I Author: Scott Adams Publisher: Adventure International

Title:TimeSet Year: 19xx Model: I Publisher: Alpha Product

Title:TString Year: 19xx Model: I Publisher: Alpha Product

Title:Veterans Ball Turret Gunner Year: 1979 Model: I Publisher: Instant Software Catalog Number: IS0051R

Title:Z-Chess III Year: 1980 Model: I Publisher: Adventure International

March 23, 2026 - New Tandy Scans

Gary K has kindly provided some additional scans. I have not looked to see how they differ, but more is always better!

Title:RS-232-C InterfacePublisher:TandyYear:1978Size:1,961,176OCRed:YesNotes:26-1145 / Black Cover / Set 2

Title:Tandy Technical Bulletin Notes and JumpersPublisher:TandyYear:1991Size:11,669,281OCRed:YesNotes:Set 2

Thank you, Gary!

March 21, 2026 - TRS-80 Trash Talk Live # 48

The next TRS-80 Trash Talk live show is Saturday, March 21, at 6:00PM Pacific Daylight Time / 9:00PM Eastern Daylight Time!

You can watch on the TRS-80 Trash Talk channel: https://www.youtube.com/channel/UCXkGugvdCkpkMDylVQb9gfg

If you want to participate in the live zoom session, reach out to trs80trashtalk at gmail dot com for information.

March 15, 2026 - Site Updates

  • The Model III NEWDOS/80 v2.0 Commented Disassembly is now complete. You can find the main page here.

March 14, 2026 - Article on Recovering S.C.A.P.

Terry Stewart has written up a very nice article about his restoration of Dick Smith's Stock Control and Pricing program.

March 11, 2026 - Site Updates

  • Paid another US$80 to get some more Dutch and French TRS-80 manuals and books sent over. Will scan and post once they arrive from Belgium.
  • Thanks to the versatility of CSS3, added a little floppy disk icon (💾) after download links throughout the site to further identify that they aree downloads.

March 11, 2026 - TRS80Tools Updated to v2.8.6


Lawrence Kesteloot has released an updated copy of his trs80tools, now new version 2.8.6.

I don't know every change, but I know what he has been helping me with - trying to find a PC based TRS-80 disassembler that can come up with comparable output to a TRS-80 based one. In this regard his changes were:

  1. Handle .SYS files that are raw dumps of floppy boot sectors. These work with the info, hexdump, and disasm commands.
  2. Add --full and --data-comment flags to the disasm command.

The updated version can diassemble SYS files, including those without standard CMD file markers (like BOOT/SYS), and with the right command line options, can produce a listing file just like DISASSEM/CMD (with the address, hex, op code, and ascii in fixed columns).

You can download it for the Windows, Mac, and Linux at https://www.my-trs-80.com/tool/#installation.

And for those who want this kind of output there are a LOT of flags to override default behavior. I used
trs80-tool disasm --data-comment --upper --full --no-labels --listing --no-known --hex-format h