Projects for the Heath-Zenith
Z-100 8080/8088 Dual-CPU Computer
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Gemini Board PC Emulator for the Z-100
Gemini Board: Photo courtesy of Steven Vagts of Z-100 LifeLine The Gemini Board was a PC emulator circuit board designed to plug into the Z-100 motherboard and provide better IBM-PC compatibility mainly at the BIOS level. The board had a separate 8088 processor dedicated to handling BIOS and video compatibility.
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Z-100 Fan Replacement
All of this noise from such a little fan. The stock fan inside of the Z-100 power supply is a 12 volt Panasonic Panaflo FBP-08B12H with an airflow rating of 32.9 CFM (Cubic Feet per Minute). The acoustical noise rating is a stunning 39 dbA! While the stock fan moves a
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The Definitive Z-100 Software Archive
After months of 19.2K and 38.4k serial data transfers, I now present to you a Z-100 software and manual archive like no other on the Internet. The bulk of my Z-100 manuals have been scanned and OCR’d and all 232 5 1/4″ and 8″ disks have been digitally archived for
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High Speed Imp v2.46
With my collection of CP/M systems growing, I decided to make my high speed version of IMP platform independent. I’ve removed the hardware-specific code from the main program but kept the code changes to support baud rate tables up to 115k. This means you can apply any existing IMP overlay now as
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Serial Port Interfacing to the Z-100 – Part 2 (CP/M 2.2)
Establishing a serial link in CP/M 2.2 was a little bit more challenging than on the ZDOS side of things. There were no CP/M terminal programs on disk so I had to download a CP/M terminal program with a ZDOS client first onto a DOS floppy, then use a program
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Serial Port Interfacing to the Z-100 – Part 1 (ZDOS/MS-DOS)
Sleep! Serial Port Interfacing in ZDOS With a fully functional Z-100, the next step was to configure one of the Z-100’s serial ports to interface with my MacBook Pro laptop so that I could begin transferring files between the two systems. I wanted to be able to both archive
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Z80Pack CP/M Emulator and NZ-COM
Z80Pack by Udo Munk is a great CP/M emulator. It will emulate a number of hardware architectures including the Altair and IMSAI systems, but I primarily use it CP/M development environment. I can quickly write or edit CP/M programs and on my MacBook and then transfer them over to my Kaypro or
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Repairing an 8″ Floppy Drive
When I first powered up the Z-100 for testing, everything worked except one of the 8″ disk drives, a Tandon TM848-1E. The drive light would make three short flashes, then one long flash and was not detected by the OS (neither CP/M nor MS-DOS). The Tandon manual didn’t list this particular blink