[Coco] Prototype/Breakout Board

Darren A mechacoco at gmail.com
Sat Mar 24 22:11:49 EDT 2012


On Sat, Mar 24, 2012 at 6:50 PM, Louis Ciotti wrote:
> I am probably just going to bring them all out.
>
> Dummy check time... .I want to make sure I have the pin/signal types
> correct.
>
> A0-A15    Bidirectional
> D0-D7     Bidirectional
> HALT      Output
> RESET     Output
> Q         Output
> E         Output
> CART      Input
> CTS*      Output
> SCS*      Output
> SND       Input
> SLENB     Input
> R/W*      Output
> NMI       Input
>

HALT* is an Input to the CPU.

The address lines could probably be treated as outputs. I think they
can only be inputs when E and Q are both low, or when the CPU is
halted.

CART*, NMI*, HALT* and SLENB* are typically driven by open collector outputs.

SND is an analog signal and should not be digitally buffered.

Darren



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