TRS-80 Model 1 Emulator Page
Last updated May 11, 2001


This program emulates a complete TRS-80
Model 1 configuration including:
Z80 Micro-Processor running at 1.774 MHZ
12k ROM memory
4k, 16k, 32k & 48k memory options
1k video memory, 64 by 16 screen with double-wide mode
Lowercase Option
Standard keyboard
Cassette port sound
Creation of real cassette tapes loadable on a TRS-80
Expansion Interface with:
 - Real time clock interrupt (40hz)
 - 100% compatable WD1771 floppy disk controller
 - Parallel printer port (memory mapped)
 - RS-232 Port
Full support of the Percom or Radio Shack WD1791 double density options
3 double-sided & 1 single sided double-density 80+ track drives
100% compatible RS WD1010 hard disk controller
4 hard drives w/up to 8 heads and 1024 cylinders each
CCR-81 cassette recorders:
 - Virtual recorder saves & loads from
   virtual cassette files
 - Wave recorder saves & loads from Wave sound files
Orchestra-85 stereo music
VS-100 voice synthesizer
In addition to the standard TRS-80 configuration the emulator also supports:
A point & shoot configuration screen with: 
 - Unlimited configurations selectable at start-up 
 - All system options and virtual disks saved on exit
A point & shoot virtual floppy selection screen with: 
 - Ability to open and create new virtual disks 
 - New & powerful virtual disk format able to do 
   everything a real  floppy disk can do 
 - Able to read & write other emulators JV1 & JV3 disks 
 - Ability to boot, read, write & format REAL TRS-80 
   floppy disks in a compatible PC drive
A point & shoot virtual hard disk selection screen with: 
 - Ability to open and create new virtual hard disks 
 - Virtual hard disk format compatible with existing virtual
   disks and other emulators virtual disks.
A virtual cassette control screen with:
 - Ability to open and create new virtual cassettes
 - Controls just like a real cassette recorder
 - 250 & 500 baud rate selection
 - Feature to force cassette motor on
 - Creation of real cassette tapes loadable on a TRS-80
A Audio/Wave cassette recorder control screen with:
 - Ability ot open and create new audio Wave files
 - Controls just like a real cassette recorder
 - Ability to load real TRS-80 tapes using SB line input
 - Ability to save cassette port output to Wave file
 - Ability to load Wave file recordings of tape programs
 - Feature to force cassette motor on
3 user selectable fonts (early, later & Lowercase Option)
2 user selectable keyboard layouts (PC & TRS-80)
 - Keyboard layouts are files which can be user modified
   to create custom keyboard layouts
Ability to save & load system snapshots
Ability to load and/or execute /CMD files directly from a PC directory
Ability to drop to a DOS prompt
Emulator speeds are accurate to .01% of a real TRS-80's for true sound and game play, plus:
 - Hot-key speed selection of 1, 1.774, 4, 8 MHZ & Turbo
 - Turbo speed is limited only by your PC's speed
 - An override speed can be set & locked so the TRS-80
   runs at user selected speeds transparent to TRS-80 OS.
Emulated LDOS & LS-DOS compatible hard drives for
faster hard disk access.
 - For use when hardware compatible hard drives aren't
   needed and higher speed is desired.
 - Up to 8 drives can be mounted at one time.
Hardware clock (port mapped w/utilities)
PC mouse support (port mapped)
PC Joystick support (port mapped)
PC to TRS-80 file I/O (port mapped w/utilities)
Enhanced instruction set including instructions to: 
 - Open, close, read, write PC files 
 - Read, change & display the PC directory 
 - Advanced mouse support w/drivers 
 - Execute DOS commands
 - 8, 16 & 32 bit multiply and divide functions
 - Ability to read and write to PC I/O ports & memory
Amplifier for cassette & Orchestra-90 sound: 
 - PC speaker 
 - SoundBlaster 16/32 ISA

System Requirements: 

  • A Pentium 75mhz compatible system
  • 640k memory w/512k free
  • VGA card 
  • MSDOS 6.x or Windows 95/98

Optional Requirements: 

  • Pentium 166mhz, for 8mhz operation
  • SoundBlaster SB16 or SB32 or 100% ISA/PCI, DOS compatible card 
  • DOS or Windows compatible Mouse 
  • DOS compatible Joystick

Download Emulator

Version 6.20

TRS-80 Model 1/III/4 Computer Software

I have scanned and preserved a large quanity of TRS-80 software and documentation.

TRS-80 Software Pages

TRS-80 Model 1/III/4 Emulator Documentation

The documentation should answer most questions about the emulator's functions.

The following link will take you to the TRS-80 Model 1/III.4 emulator on-line documentation:


Enhanced Z80 Instructions

The emulator has a set of enhanced Z80 instructions. These instructions allow TRS-80 programs to interface with the PC's disk drives, ports, memory and other hardware. These instructions also add high level math functions to the Z80 instruction set.

NOTE: These instructions are only available in the emulators.

The following links contain a list of the enhanced instructions and documentation for each instruction.

Enhanced Instruction Documentation (on-line)

Enhanced Instruction Documentation (Microsoft Word 119k)

TRS-80 Model 1/III/4 Emulator News

Version 6.20 contains one error fix and several enhancements.

Version 6.10 contains some more bug fixes that slipped by plus a couple of additional features.

The documentation for the Enhanced Z80 Instructions has been corrected and documentation for the new 'Speed Set' instruction has been added.

Old TRS-80 Emulator Update News