Re: Speed check

[Sheldon Simms <sheldonsimms@yahoo.com>]

On Wed, 20 Aug 2003 16:57:44 +0000, Wayne Stewart wrote:

> 
> 
> Sheldon Simms wrote:
> 
>> As soon as I read the original post, I whipped out my soldering
>> iron and went to work. I socketed the oscillator and then started
>> trying out different speeds. For me, the fastest working oscillator
>> is 32 Mhz. At 40 Mhz it almost works, but crashes into the monitor
>> at startup.
>> 
>> I don't think the SRAM is a problem here, at least on my IIc+.
>> Mine has 12ns SRAMs built in and that should be good enough for
>> a 64 Mhz oscillator at least.

> I think you'll find that that SRAM is 100ns, not 10ns but I don't think
> that that's the bottleneck.

You are right. The SRAMs I have are Hitachi HM6264ALP-12. I just stupidly
assumed that was 12ns when it's actually 120 ns. Well I will go ahead
and put in some faster SRAM and see if I can get at least the 40Mhz
oscillator working.

I would like to try a faster 65c02 too. It would be really nice to get
this IIc+ going at 16 or 20 Mhz.