2K Z80 Monitor Program for Microbyte MZ80A-IO

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Project Description

This program is a custom 2K eprom monitor routine that runs on a Z80 cpu card in the top 2K of memory space. This particular version runs on a Microbyte MZ80A-IO cpu card. It uses several pieces of hardware on other boards in the system. The system console uses the serial port (ports 2,3) on an IMSAI MIO serial/parallel/cassette tape board. Sample serial code is also included that accesses the 2 serial ports on the MZ80A-IO CPU card. A second big section of code is used for booting CPM from a parallel port interfaced SD card disk interface. Details will be revealed on another web page that is currently under construction. This parallel port micro SD card disk is interfaced through a port on the IMSAI MIO card. A 64K ram card with the top 2K disabled is used in the system for RAM.


System Requirements

The hardware setup:
- The Microbyte MZ80A-IO Z80 CPU card.
- Tanner 64K static ram card.
- The IMSAI MIO serial/parallel *2/ cassette interface card.(optional)
- The optional BUSMON card for debugging and blinking lights.(optional) s100-busmon project


Electrical Drawing(s)

MZ80A-IO Jumpers - mz80a-conf.pdf (45kB)


Source Code

Z80 Source Code - MZ80A-IO.Z80 (42K)
Intel Hex Eprom Image - MZ80A-IO.HEX (5K)
The eprom image is burnt into a 2716 EPROM located on the MZ80A-IO CPU card.

The following 2 files are a standalone monitor that runs strictly on the MZ80A-IO card (does not support booting to CPM).
Z80 Source Code - MZ80MON.Z80 (32K)
Intel Hex Eprom Image - MZ80MON.HEX (4K)
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