Introduction to Emulators and DMK’s

Quick Start Guide to TRS-80 Emulation

Overview

This comprehensive guide will help you get started with TRS-80 emulation, from choosing the right emulator to running your first programs. Whether you’re completely new to emulation or looking to work with disk images, this guide covers everything you need to know.

What you’ll learn:

  • How to choose and set up a TRS-80 emulator
  • Working with ROM files and disk images
  • Loading and running programs from cassette and disk
  • Managing disk images with modern tools
  • Setting up hard drive emulation

Note: This guide assumes you already know how to use a TRS-80. If you need help with TRS-80 basics, see the reference manuals linked at the bottom of this page.

Section 1 – Basics of Emulation

Part 1 – Choose Your Emulator

Two emulators stand out as the most complete and reliable options: TRS80GP and TRS32. Both are excellent choices with different strengths. Use this comparison table to determine which best fits your needs:

Emulator Comparison
Feature
vs
Cross-platform (Linux, Mac, Windows)
✓
✗
Completely free
✓
✗
Built-in ROM files
✓
✗
Authentic scanline display
✓
✗
100% GUI interface (Windows)
✗
✓
Model III High Speed Tape support
✓
✗
WAV file cassette input
✗
✓
EPSON graphics printing
✗
✓
Wait state emulation (0/1/2)
✓
✗
Alpha Technology memory boards
✗
✓
MEM series boards
(HyperMEM, SuperMEM, MegaMEM)
✓
✗
Joystick support
Trisstick
Alpha Products
Light pen emulation
✓
✗
Electric Crayon emulation
✓
✗
Stringy Floppy emulation
Exatron & Aculab
✗
Speed-up board emulation
✗
Archbold only
Clock/calendar emulation
✗
Smartwatch, NEWCLOCK/80
Custom character sets
✓
✗
RS-232 pass-through
Internet
Serial port
Omikron Mapper emulation
✓
✗
Alternative disk formats
HFE, IMG
✗

Shared Features: Both emulators support machine state saving, ORCHESTRA 80/85/90, mouse emulation, hard drives, and most common TRS-80 peripherals.

Next Steps: Download your chosen emulator and either install TRS32 or extract TRS80GP to a directory of your choice.

Part 2 – ROM Files

TRS80GP

Includes built-in ROMs for:

  • Model I
  • Model III
  • Model 4
  • Model 4P

No additional ROM files needed – ready to run out of the box!

TRS32

Requires separate ROM files:

  1. Search for david keil emulator download
  2. Download the older emulator package
  3. Extract ROM files to a directory
  4. In TRS32: OPTIONS → Image Path
  5. Point to your ROM directory

Part 3 – Windows Basics for Beginners

Skip this section if you’re comfortable with: Unzipping files, creating directories, copying files, and using the command prompt.

For those who need help with Windows file management, here’s a step-by-step guide to setting up TRS80GP:

Step-by-Step Setup
  1. Create a directory:
    • Right-click on your C: drive in Windows Explorer
    • Choose New → Folder
    • Name it trs80
  2. Download TRS80GP:
    • Save to C:\trs80 if your browser allows
    • Otherwise, download then move the file there
  3. Extract the emulator:
    • Double-click the downloaded file
    • Right-click trs80gp.exe
    • Choose Extract to C:\trs80
  4. Add your disk images:
    • Copy any DMK files to C:\trs80
  5. Open command prompt:
    • Start Menu → Windows System → Command Prompt
    • Type: CD \trs80 and press Enter

Part 4 – Starting Your Emulator

TRS32 (GUI Method)

Simply double-click the TRS32 icon to launch the emulator with a graphical interface.

TRS80GP (Command Line)

Open a command prompt, navigate to your TRS80GP directory, and use command-line parameters. Full documentation available at the TRS80GP website.

Part 5 – Getting to BASIC vs DOS

For Cassette BASIC (Non-DOS)

To reach the READY prompt for loading cassette programs:

TRS32 Process
  1. Double-click the TRS32 icon
  2. You’ll see a blank screen
  3. Hold ESC + press SHIFT + F8 (cold reboot)
  4. You’ll see MEMORY SIZE?, MEM SIZE?, or CASS?
  5. Press ENTER for memory size, or H/L for high/low speed cassette
TRS80GP Command Line
  • Regular speed: trs80gp -m1 -dx
  • Turbo speed: trs80gp -turbo -m1 -dx

Note: TRS80GP bypasses the memory size question by default. To see it, add -nlc to disable the lowercase driver.

Loading Cassette Programs

TRS32
  1. Press F9 to select your cassette file
  2. Press CTRL + F9 then click PLAY
TRS80GP
  • GUI: Cassette → Insert and choose your file
  • Command line: trs80gp -m1 -dx -c filename

Booting into DOS

TRS32
  1. Press F6 and select your boot disk image
  2. Press SHIFT + F8 to cold reboot
TRS80GP Examples
  • Custom disk: trs80gp -m1 -d0 boot.dmk
  • TRSDOS v1.3: trs80gp -m1
  • LDOS v5.3.1: trs80gp -m1 -ld
  • Model III: trs80gp -m3 -d0 boot.dmk
  • Model 4: trs80gp -m4 -d0 boot.dmk
  • Multiple drives: trs80gp -m3 -d0 boot.dmk -d1 data.dmk

Tip: Add -turbo after trs80gp for maximum speed.

Part 6 – File Types and Extensions

Understanding TRS-80 file extensions helps you know how to run programs. Since users could name files however they wanted, these are the common conventions:

BASIC Programs
  • .BAS – Standard BASIC file
  • (none) – Often BASIC or data
  • .ASC – ASCII BASIC file

To run: Enter BASIC, then RUN”filename” (or RUN”filename/” in LDOS)

Machine Language
  • .CMD – Executable program
  • .CIM – Core image dump
  • .ExE – Model 4 port (needs ExEC)

To run: Just type the filename (no extension needed for .CMD files)

System Files
  • .OVL, .OV1, .SYS – Overlay files
  • .JCL, .BLD – Batch files
  • .LBR – Library archive

Usage: Required by other programs or run with specific DOS commands

Development Files
  • .ASM, .SRC – Assembly source
  • ??Z – Squeezed files

Usage: Require assembler or unsqueeze utility

Emulator Files
  • .DMK – Disk image
  • .DSK – Disk image
  • .CAS – Cassette image

Usage: Mount in emulator

Part 7 – TRS-80 Operating Basics

Non-DOS (Cassette) Operations

Identifying tape contents: Without DOS, you can’t easily see what’s on a cassette. Use these tools:

Loading BASIC Programs
  1. Type CLOAD and press Enter
  2. When loading completes, type RUN
Loading SYSTEM Programs
  1. Type SYSTEM and press Enter
  2. At first *? prompt: enter filename
  3. At second *? prompt: type /

Loading Indicator: Watch for two “*” symbols in the upper right corner (one blinks). Both emulators show tape counter progress. If the counter stops without completing, the load failed – check filename, speed, or file integrity.

DOS Operations

Running BASIC Programs
  1. Type BASIC and press Enter
  2. Answer any prompts
  3. Type RUN”filename/bas”
Running CMD Programs
  1. At DOS prompt, type the filename
  2. Press Enter (no .CMD extension needed)
Directory Commands
  • Drive 0: DIR :0
  • Drive 1: DIR :1

Section 2 – Working with Disk Images

Part 1 – TRSTools for Disk Management

The essential tool for managing TRS-80 disk images is TRSTools, a Windows utility that works like Windows Explorer for virtual disks.

TRSTools Capabilities
File Operations
  • Drag and drop files between TRSTools and Windows
  • Add, extract, rename, and delete files
  • Preserve original file dates
  • Change disk labels and volume dates
Disk Management
  • Open existing disk images
  • Create new virtual disks
  • View disk properties and DOS type
  • Check NEWDOS/80 PDRIVE information
Integrated Viewer
  • View BASIC files as ASCII text
  • Disassemble CMD files
  • Display high-resolution pictures
  • Verify file integrity

Download: TRSTools v1.13 Download

Part 2 – Understanding Disk Image Codes

When I read disk images for users, I include damage codes in the filename to indicate any problems found:

[Tx-a b c d e]

Track x has bad sectors a, b, c, d, e

Example: [T5-2 7 15] means Track 5 has bad sectors 2, 7, and 15

[Txsy-a b c d e]

Track x, Side s has bad sectors a, b, c, d, e

Used for double-sided disks

[Tx-Align]

Track x reported non-standard sector count

Example: Model III disk showing 17 sectors instead of 18

Checking Damaged Files:

  1. Use TRSTools to examine individual files on the disk
  2. Corrupted .CMD or .BAS files will appear as garbage in the viewer
  3. For detailed analysis, use SuperUtility with DMKCheck
  4. Use FILE LOCATIONS (Menu 8 → 7) to see which files were affected by bad sectors

Section 3 – Hard Drive Setup

Setting up hard drive emulation requires specific steps for each emulator. Here’s the complete process:

Initial Setup

  1. Create a directory for your emulation files
  2. Download Hard Drive Operating System v6.02.00
  3. Extract the ZIP file to your directory
  4. Rename the initialization disk to boot.dmk:
    “Hard Drive Operating System v6.02.00 (1984)(Logical System)[M4][Original][Set 1][Initialization].dmk”

Emulator-Specific Steps

TRS32 Setup
  1. Launch TRS32
  2. Choose File → Autostart
  3. Select boot.dmk
  4. Press F7 for hard drive image
  5. Enter filename for new hard drive
  6. Click YES to create
TRS80GP Setup
  1. Navigate to your boot.dmk directory
  2. Run command:
trs80gp -m4 -turbo -h harddrive.hdv -d0 boot.dmk

Hard Drive Configuration

Once the emulator starts, follow these prompts in order to configure your hard drive:

Configuration Steps (Follow in Sequential Order)
Step 1: Initial Setup
  1. Enter the date
  2. BASIC + Enter
  3. RUN”HARDGEN/BAS” + Enter
  4. Is your system ready? Y + Enter
Step 2: Drive Configuration
  1. How many floppy drives are connected? 4 + Enter
  2. How many hard drives are connected? 1 + Enter
  3. Serial Number: Enter any 5-digit number
  4. Did you enter all the serial numbers? Y + Enter
Step 3: Disk Configuration
  1. Number of Megabytes: 10 + Enter
  2. Press any key when ready to continue: Enter
  3. How many logical drives: 8 + Enter
  4. How many floppy drives? 4 + Enter
Step 4: Advanced Options
  1. Do you want to reserve a local drive? N + Enter
  2. How many logical drives do you want to use? 1 + Enter
  3. Do you want to change any value? N + Enter
  4. Which Method do you Prefer? A + Enter
Step 5: Final Setup
  1. Press any key when ready to continue: Enter
  2. Do you want the hard disk to be the system device? Y + Enter
  3. Is the configuration correct? Y + Enter
  4. Enter the Disk Pack name? Press Enter (default)
Step 6: Formatting Process
  1. Enter the Master Password? Press Enter (none)
  2. To Proceed, type “YES”? YES + Enter
  3. Wait for formatting and verifying to complete
  4. Press Enter when formatting is done

Disk Swapping Process:

  1. System will prompt to swap disks – remove boot.dmk from drive 0, insert the DOS disk from the ZIP file
  2. Press Enter to continue installation
  3. When prompted again, remove the DOS disk and put boot.dmk back in drive 0
  4. Press Enter to complete setup

Final Result: Start the emulator with trs80gp -m4 -turbo -h harddrive.hdv -d0 boot.dmk to run with the hard drive as drive 0 and boot disk as drive 4.

Reference Materials

Operating System Manuals

Need More Help?

Support and Feedback

If you’re new to TRS-80 emulation and have questions not covered in this guide (excluding general TRS-80 operation questions), please contact me and I’ll update this page with additional information.

This guide covers:

  • Emulator selection and setup
  • ROM and disk image management
  • Basic emulation operations
  • Hard drive configuration

For TRS-80 operation help: Consult the reference manuals linked above or other TRS-80 documentation resources.