Just an update to note that I was successful in reading the ROM out of
the MOS 6500/1 using the test mode. I used an ATMEGA32 to drive the
opcodes into PORTC, driving the RESET line to 10V, and reading data from
the PORTA on the unit. The opcodes loaded data from the ROM and put it
on the PORTA as output.
I dumped both the CBM 1520 Plotter ROM versions (-01 and -03).
Jim
--
Jim Brain
brain at
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