Hello Gerrit, > The large > drives use two 6502 running on the same clock speed, but 180 degrees > out of phase (kind of like the 6510 and VIC in a C64). They use the > same data bus while the address bus is seperate and only a certain > part of the RAM can be seen by both CPUs. > > To make that work, all chips used on that construct must have PHI2 of > the CPU they are working with as part of their enable signal. > Otherwise it would happen that 2 chips are active at the same time > and fight over the data bus. > > It's a simple way to make 2 CPUs work together without getting in the > way of each other while still being able to share data. Yes, it's true. I forgot this argument at the night i wrote the answer to ruud. But i think, there was more than this error. The address logic was very strange. Greetings Martin Message was sent through the cbm-hackers mailing listReceived on 2013-10-11 01:00:13
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