RE: External KERNAL using a 6510

From: COPLIN, Nicholas. (
Date: 2000-08-30 10:35:47

> If this construction works or not, the fact that they used a 6510 in this
> way 
> completely suprised me. I wonder how you feel.
[COPLIN, Nicholas.]  Its very interesting indeed.  

I've often wondered how an external device could write to the C64's RAM....
I figured reading is easy enough as you just latch on the edge of the Phi2,
but putting data on the bus and writing it has always confused me... if you
pull DMA low and monitor the BA you can work out when to put data on the bus
during Phi2, but how does one delay the Write=low signal?  The circuit still
seems to use the internal R/W line... is there a wait to avoid it... 

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