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GWMON-65 Small Monitor


Veteran Member
Feb 1, 2010
Central VA
I think it's finally ready to be poked at:


This is a monitor that follows the same command syntax and input/output formatting as GWMON-80, our small monitor for 8080 and compatible systems. It's not really a straight-across port as parts were rewritten to take advantage of the 6502, rather than trying to cram 8080 patterns into 6502 syntax.

The monitor has four basic functions: Dump memory, Edit memory, Go to address, and Load Intel HEX data. The README covers command syntax. The D command output is parseable by SRecord's -hexdump option.

GWMON-65 SM with Motorola 6850 I/O initialization and reset/NMI/IRQ vectors fits in 512 bytes, which means it'll work with very old systems like the Ohio Scientific 400 board, which uses two 1702A 256-byte EPROMs.

Like GWMON-80, GWMON-65 is modular, to make it easy to create new customizations for systems.

Feedback appreciated!