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WOZ monitor on TTL

A project log for Gigatron TTL microcomputer

"Just because", a microcomputer that runs without a microprocessor

Marcel van KervinckMarcel van Kervinck 06/12/2018 at 20:050 Comments

I've ported the Apple-1 built-in monitor program: WozMon.gcl

The original is 254 bytes, my version is $254 bytes . About half of that is for terminal output (character printing). The Apple-1 had dedicated hardware for that... With this, all original Apple-1 firmware has been ported to the Gigatron :-)

Now you can inspect memory locations, write to them and execute code.

Tutorials for the original WozMon, such as this nice one, are applicable as I tried to deviate as little as possible from the original: the differences are essentially cosmetic or slightly improved usability. The Gigatron-specific differences are:

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