Society of Eight-Bit Heathkit Computerists

A web site dedicated to preserving the Heathkit 8 bit computers


Operating Systems
HUG Library
Application Archive
ROM Images
Cassette Tape Images
Dazzle Star Disassembler
Don Maslin Archive

Operating Systems

CP/M 2.2.02 Distribution (2 disk images - 70 KB)

CP/M 2.2.03 Distribution (3 disk images - 89 KB)

CP/M 2.2.04 Distribution (4 disk images - 131 KB)

CP/M 2.2.03 Bootable with BIOS-80 installed (1 disk image)

CP/M 2.2.0X Distribution for H37 Soft Sector (4 IMD disk images)

CP/M 3.0 Distribution for MMS Corvus (zip 325 KB)
CP/M 3.0 MMS Corvus Source Files (zip 200 KB)

DG Electronics 32K CP/M 2.21 (1 disk image)

HDOS 1.0 Distribution (2 disk images - 102 KB)

HDOS 1.5 Distribution (1 disk images - 53 KB)

HDOS 1.6 Distribution (3 disk images - 109 KB)

HDOS 2.0 Distribution (3 disk images - 122 KB)

HDOS 2.0 HOS-5 Update for H-37 (1 disk image - 48 KB)

The following 3.0 distribution is in H-37 SS/SD format
HDOS 3.0 Distribution (7 disk images - 248 KB)
(Note: below files were converted from the original H-37 distribution files above and includes a bootable H17 disk image)
HDOS 3.0 Distribution for H17 controllers (8 disk images - 302 KB)

The following 3.02 distribution has been converted to H-17 hard sector format from copies submitted by Norm Sokol
HDOS 3.02 Distribution (8 disk images - 259 KB)

HSY Device Driver Source Files (zip 15 KB)

Heath/Zenith H-37 Diagnostic and Conversion Utilities Disk (1 disk image - 50KB)
Part# 448-412A
The H-37 Diagnostic disk is a self-booting disk that tests the H-37 controller card. It was included with the original H-37 controller card kit.

CP/M for the SVD
Bootable disk images for use with the Semi-Virtual Disk (SVD)
CP/M 2.2.03 62k ZCPR for GIDE (zip 2 disk images, 124KB)
CP/M 2.2.03 thru 2.2.04 Standard + H37 (zip 19 disk images 1MB)

HUG Application Library

This archive contains all of the HUG Library (part numbers 885-xxxx) that we were able to acquire. I will update the library as more disk images are added.

HUG Library (zip 107 disk images, 3.5 MB)
HUG Library Contents

Soft Sector disk images were created using Dave Dunfield's IMD V1.17

HUG Public Domain Disks 1 through 5 (Double Sided/Soft Sector)

Application Archive


SEBHC Complete Set Volume 1 (233 disk images - 9.1 MB)
Volume 1 Contents

SEBHC Complete Set Volume 2 (126 disk images - 4.9 MB)
Volume 2 Contents

SEBHC Complete Set Volume 3 (80 disk images - 2.6 MB)
Volume 3 Contents

SEBHC Complete Set Volume 4 (104 disk images - 3.8 MB)
Volume 4 Contents

SEBHC Complete Set Volume 5 (71 disk images - 2.7 MB)
Volume 5 Contents

Volume 6 contains a collection of software from Skip Chambers that includes modified versions of HDOS. They are called OMDOS, or One Module HDOS, and SmallDOS. There are DOC files on the disks that explain the differences and how to set up a version of this OS on your Z80 H8 or H89 system.

Volume 6 contains some high capacity (up to 200K) disk images and requires H8DIMGR and the H8D Utility 1.51.
SEBHC Complete Set Volume 6 (47 disk images - 2.5 MB)
Volume 6 Contents

Volume 7 contains some high capacity (up to 400K) disk images and requires H8DIMGR and the H8D Utility 1.51.
SEBHC Complete Set Volume 7 (67 disk images - 4 MB)
Volume 7 Contents

SEBHC Complete Set Volume 8 (32 disk images - 2.5 MB)
Volume 8 Contents

Hardware/Software Virginia rescue by Glenn Roberts
SEBHC Complete Set Volume 9 (82 disk images - 3.4 MB)
Volume 9 Contents

DG-Super89 Software Disk System Emulator (1 disk image - 14 KB)
DG-Super89 Disk Contents

Empty Disk Images (8 empty disk images - 23 KB)

C80 3.0 Mathpack for HDOS Distribution (ZIP H8D disk image)
C80 3.1 for HDOS Distribution (ZIP disk 1 and 2 H8D disk image)
C80 for CP/M (ZIP 3 H8D disk images)

SDT for CP/M (ZIP with 2 files)
SDT Documentation (PDF)

Skycastle Computer Products GTF for the CP/M H89 (200 KB zip)


H8D Utility by Les Bird
A utility program to help manage H8D disk image files. Includes a somewhat stable (but still being tweaked) release of my H89 emulator.

Boot Images for the H8D Utility H89 emulator (CP/M 2.2.02,03 and 04 plus 03-BIOS80 w/ZCPR, HDOS 1.6, HDOS 2.0, HDOS 2.0 w/HSY and HDOS 3.02)
XNA run-time for the H89 emulator (7.5mb)
XNA is Microsoft's managed DirectX run-time for C# applications which I use for rendering the output of the H89 emulator. You should install this package if you don't already have it.
H8D Utility C# Source Code for Visual Studio 2010

H8DIMGR disk transfer utility for 100K, 200K and 400K hard sector disks (HDOS and CPM) (8080 ASM Source Code)
H8DIMGR is a utility by Les Bird that runs on a Heathkit computer and transfers hard sector disk images of any type via a serial port to the H8DUtility V1.51 or later running on a PC. H8DIMGR is the preferred method for sending disk images (instead of SDUP-SP) as it will work with any hard sector disk type, HDOS or CPM, 100K, 200K or 400K, and will automatically detect the disk type. To use this utility download the file from the link above then transfer the disk image to a Heathkit computer using H89LDR or the H8DUtility. Boot with the new disk and run H8DIMGR2.ABS then launch H8DUtility V1.51, click the CREATE button then click the Client Status button. If you have a good serial connection then you should see "Client is ready" in the H8DUtility log and can now send or receive disk images to the Heathkit computer.

Disk Image Utility Disk Image Utility by Darrell Pelan designed to support using Flash Floppy or HxC flashed Gotek drives with Heathkit 1980 era computers.
It supports the native disk formats using IMG files and allows you to extract and add files from your PC to the disk image file.
It currently supports CP/M, HDOS, and MS-DOS FAT12 formats used by the H-8, H-89, and Z-100. The zip file includes setup files and a manual

Vinculum (USB) Utilities Ver. 4.0 by Glenn Roberts - February 2022
File transfer tools for use with USB (VDIP1)

CP/M (H8D)

H8Trans for Linux by George Farris
A Linux utility to transfer H8D disk images to/from a real Heathkit computer via a serial link.

H89LDR9 Disk Image Transfer Program Version 9 by Dwight Elvey
Creates images of disks by transfering from the H8/H-89 to a host program running on a DOS-based PC.

H89LDR9 Patch by Dan Johansson
Modifies H89LDR9 to work with the H-89 serial port 320Q instead of 340Q.

HDOS Disk Analyzer V1.04 by Paul Laba
An excellent Excel extension that tells you everything you need to know about HDOS disk images. Includes the ability to view and export individual files.

EMULATE by Peter Shkabara
Allows the H8/H-89 to read the formats of other CP/M computers. Source code is included.

Disk Dump by  David Shaw
Creates disk images in ASCII format by capturing the data with a terminal program on your PC. Supports drives up to 2 sided and 80 tracks.

IMD V1.17 by Dave Dunfield
Creates soft sector disk images from a DOS PC.

CP/M to HDOS file transfer utility disk
CPM2HDOS.ZIP (1 disk image)

Patch for MAPLE.ABS to change I/O port from 330Q to 340Q


HDOS 3.02 H17DVD and H17INIT for Heath assembler
H17DVDr0.H8A (ZIP)

Dr T Diagnostics Disk (ZIP)


ROM images

ROMs compatible with the MESS emulator:

H8 ROMS (444-13_PAM8, 444-13_PAM8AT, 444-13_PAM8GO, 444-19_H17, 444-70_XCON8, 444-140_PAM37)
H8 ROMS for the Dave Wallace emulator.


H-88/H-89/Z-90 ROMS (444-19_H17, 444-62_MTR89, 444-84_MTR84, 444-142_MTR90 and MMS84A)

Super-19 for the H-19 terminal
Super-19 Documentation

H-19 ROMs (444-29 Font, 444-37 Keyboard, 444-46 Code)

SUPERSET ROMS for the H-19/H-89 (101-422 keyboard, 101-402 code, 101-431 font)
SUPERSET Documentation

Bob Groh transcribed the source listing for the H17 ROM (444-19) which was slightly touched and verified to compile by Dan Emrick:
Heath Source Listing is here (HOS1SL_2_07_SYDD.PDF 3.5mb)
SYDD source code ASM file here (ASM 106KB)

Terry Gulczynski has disassembled the XCON8 ROM (part #444-70) and added very helpful comments to make it more understandable. Eventually we will incorporate GIDE boot code into the XCON8 ROM for use with the
 H8-Z80-64 Rev 2 CPU card. The XCON8 ROM is the front panel control code for the Heathkit H8 computer. The commenting of this source file is not 100% complete but it's a good base for those who want to get started early with their own modifications.

XCON8 Source Code as of 9/22/2009

MTR90 Source Code as of 6/12/2016 by Terry Gulczynski

H-19 Disassembled ROM Source Code from Terry as of 02/20/2010
Text Document from Terry about the H-19 source code

Cassette Tape Images

Heath Tape Contents

HUG 885-1009 Tape Contents (PDF)

Don Maslin

A rare and valuable find recovered on Dec 9, 2012.

The complete (as far as I know) Don Maslin Boot Disk Archive.
Includes boot disk images for just about every old and long outdated computer ever made including several Heathkit systems. (263 mb)
Don Maslin Archive Index (PDF)

Dazzle Star Disassembler

Patched and packaged by Kenneth Owen


July 1, 2020