Talk:CPU pinout: Difference between revisions

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==Pin 30 Experiment==
==Pin 30==
Pull pin 30 high, then write either $00 or $80 to $401A and see if the sound registers come back... --[[User:Quietust|Quietust]] 04:15, 27 February 2011 (UTC)
I've managed to trace pin 30 all the way to the enables for $4018-$401A, but pulling the pin high seems to have some other effects on the $4000-$401F read/write enable signals themselves. Exactly what those effects are, I don't know - the RP2A03G seems to use both enhancement-mode and depletion-mode transistors but I don't know how to tell them apart, so I can't properly determine exactly how the circuits operate. --[[User:Quietust|Quietust]] 00:19, 20 March 2011 (UTC)
:Or perhaps not - I lost my place when tracing W$401A.D7 and ended up following the reset signal instead (which goes damn near everywhere). I suppose it would help if I knew exactly what I was looking at... --[[User:Quietust|Quietust]] 19:47, 1 March 2011 (UTC)

Revision as of 00:19, 20 March 2011

Pin 30

I've managed to trace pin 30 all the way to the enables for $4018-$401A, but pulling the pin high seems to have some other effects on the $4000-$401F read/write enable signals themselves. Exactly what those effects are, I don't know - the RP2A03G seems to use both enhancement-mode and depletion-mode transistors but I don't know how to tell them apart, so I can't properly determine exactly how the circuits operate. --Quietust 00:19, 20 March 2011 (UTC)