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G0HZU_JMR · 12th Sep 2017, 3:30 pm

I had a quick skim of the datasheet for the 6802 and it looks like it is a dedicated CPU with no internal ROM. I worked on the other variants of 680x where the chip could act as an MCU or a CPU depending on the mode pins (set during reset).

The runtime ROM was mask programmed internally as the chip ran as an MCU when in the ECU. It's still possible to dump out the ROM but it is quite fiddly to do it. But in the case of the 6802 CPU you could just read the external memory chip(s) to get the program code to see what it is supposed to do?

12th Sep 2017, 3:30 pm	#8
G0HZU_JMR Dekatron Join Date: Sep 2010 Location: Cheltenham, Gloucestershire, UK. Posts: 3,077	Re: Help with 6802 Microcontroller I had a quick skim of the datasheet for the 6802 and it looks like it is a dedicated CPU with no internal ROM. I worked on the other variants of 680x where the chip could act as an MCU or a CPU depending on the mode pins (set during reset). The runtime ROM was mask programmed internally as the chip ran as an MCU when in the ECU. It's still possible to dump out the ROM but it is quite fiddly to do it. But in the case of the 6802 CPU you could just read the external memory chip(s) to get the program code to see what it is supposed to do? __________________ Regards, Jeremy G0HZU