@Eric, All, Light a candle for those in the dark..
If the min. clock speed is dictated by the ability of the gates to hold a charge, as the bits rot away as charge drains (someone said "minimize resistance to ground", but I believe they meant "maximize"?) , then what is limiting the max. clock speed? Is it just basic PCB stuff, like trace inductance, mutual / parasitic capacitance, etc? Or are there other, more critical factors? I can't imagine propagation delays could matter at these slow speeds.. requiring meandering of traces and so forth. On Sat, May 28, 2016 at 2:55 PM, Corey Cohen <[email protected]> wrote: > > > On May 28, 2016, at 1:31 PM, Eric Smith <[email protected]> wrote: > > > >> On Sat, May 28, 2016 at 5:31 AM, Corey Cohen <[email protected]> > wrote: > >> I can't wait to buy one!!! I have a spare Replica-1 just waiting to > hook up to a Monster 6502. > > > > It doesn't run at full speed. It presently runs in the tens to low > > hundreds of kHz. If a Replica-1 can be run slower than normal, that > > might work. Other common 6502-based micros, such as the Apple II or > > Atari 400/800 will not work at low speed due to inherent timing > > requirements related to video generation and DRAM refresh. > > > >> Just need to wire up a single step switch and this thing will be > awesome!!! > > > > If you wire single-stepping using the RDY line, that should work, > > though it will only single-step read cycles, not write cycles. > > > > You can't single-step the actual clock because it is dynamic logic. > > The replica-1 uses a propellor chip for video and static ram so I don't > think it's that critical to timing. >
