commodore superpet mapping

From: didier derny <didier_at_aida.org>
Date: Tue, 1 Nov 2016 13:53:03 +0100
Message-ID: <ca226ca8-2196-e9e9-ab85-c77b05e64696@aida.org>
if I saw this machine in 1981, I never really had the opportunity to
play with it
Initially I thought the 6809 was running on it's ram and communicating
with the 6502...
(a bit like the madison zram with it's z80)

recently I found the schematics of the superpet board (combined one)
Finally  (apparently according what I saw)
1/  either the  6809  or the 6502 is running ?
       6809 stopped by the dma   ?
       6502 stopped by shutting down the power  ?
2/ the extra memory is only accessed as 16 page s of 4k in 9000 ?

3/ it add a serial port

4/ a protection dongle

Initially I thought the 6809 was running on it's ram and communicating
with the 6502...

how are the rom decoded ?  I dont really understand...
the standard rom are only 'seen' by the 6502 ?
the extra rom only 'seen' by the 6809 ? and mapped at the same place ?

--
didier





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