Hi .

Any one of you have some experience with over clocking wdc cpu ?
I had short chat with David from WDC and he said :

6502 - 65816 : can run up to 20mhz at 5v
6502 - 65816 : can run up to 16mhz at 3v3

Did anyone of you try this ?

I can't vouch for the 3.3 volt limit but I do know from experience that 20 MHz at 5 volts is not a problem. In fact, the '816's behavior suggests that 25 MHz might be within the realm of possibility. I suspect that the 16 MHz limit for 3.3 volt operation is also a little bit conservative.

If you are going to run into a problem at the high end of the clock range it'll most likely be due to timing issues with other hardware, or some sort of quirky behavior due to your board layout. Also, latching the A16-A23 component of the address becomes tricky at these speeds. Whatever does the latching has to have single digit nanosecond performance.

_________________
x86?  We ain't got no x86.  We don't NEED no stinking x86!