This Web page last updated date Oct 12 2016. copyright Herb Johnson (C) 2016. . In Summer 2016, I'm repairing some Heath Zenith H89 computers. I wanted to access H8D disk images from SEBHC, look at their directory and extract files, on and onto my desktop computer. Then I could use serial file transfers from an MS-DOS/Windows or other modern system, to my H89 to move the extracted files or disk images.
I found a C-source utility program by Glenn Roberts for use under HDOS, to read HDOS disk images. With Glenn's permission, I modified it to compile and run in an MS-DOS environment, an easy environment to program in and operate. I also rewrote the program to support CP/M hard-sectored diskettes. In both cases, these are single-sided 40 track 10 hard sectored disks which were images. The programs I've produced are crude but seem functional. I include source so you can fix or enhance them - let me know of any changes. These are not for commercial purposes, as per agreement with Glenn Roberts. - Herb Johnson
/* h8ddos - This program opens a 100K disk-image file in "H8D" format and ** performs various analyses of the disk image contents. ** It provides a menu of commands that let you: ** ** - List key information about the disk image ** - Dump key sectors such as RGT and GRT ** - Dump any specific sector (by number) ** - Print a directory listing ** - Dump the contents of a file (in hex/ascii) ** - Extract a file to the (in this case) MS-DOS/Windows environment ** ** Usage: h8dhdos [H8D HDOS file image]
Here's the H8DHDOS ZIP file with source, 32-bit MS-DOS exe, and some helpful files.
H8DCPM opens a 100K disk-image file in H8D CP/M format and ** performs various analyses of the disk image contents ** ** - List key information about CP/M file structures ** - Dump any specific sector (by number) ** - Print a directory listing ** - Dump the contents of a file (in hex/ascii) ** - Map to toggle a display of track and sectors dumped ** - Extract a file to the (in this case) MS-DOS/Windows environment ** ** Usage: h8dcpm [H8D CP/M file image]
Here's the H8DCPM ZIP file with source, 32-bit MS-DOS exe, and some helpful files.
Glenn checked the H8D archives at SEBHC, and found almost all the H8D disk images there are 100K sized. That means they are imaged from single sided 10-sectored 40 track diskettes. That seems to be the "distribution format" for Heath hard-sectored H8 and H89 software, which the H8D images represent. For other formats, you'd have to change program constants and some parts of the code. HDOS disks in other formats may have more directory sectors; CP/M disks may have different group sizes.
These C programs were compiled under lcc-win32 for the command line of MS-DOS 32-bit, and Windows MS-DOS "command prompt" window. Windows after Win NT is 32 bit. Haven't tried 64-bit Windows. Glenn wrote his C code for Software Toolworks C/80 V. 3.0 under HDOS. His source is included with the HDOS version of the programs. Chances are these C programs could be edited again and compile and run under CP/M or HDOS; or Linux too. It's pretty plain vanilla C. - Herb
...is the Society of Eight-Bit Heathkit Computerists. They've worked since the early 2000's collectively, to preserve and enhance Heath/Zenith H8 and H89 systems hardware and software. Check out their site and email list (current a Google Group) for more info. - Herb