Re: Slowest IIgs RAM

[quadrajet1@aol.com (Quadrajet1)]

 > : Does anyone know what the slowest speed 256K DRAMs that can be
> : > used in
> : > : the IIgs one meg memory card would be? If memory serves a 1 mhz
> : > 6502
> : > : needs at least 400 nanosecond chips, so I would assume 200
> : > nanosecond
> : > : chips would be a bit too slow for the card. Am I correct?
> : > :
> : > : Roy
> : >
> : > 200ns is FASTER than 400ns.
> :
> : Absolutely correct, and totally worthless.
> :
> : I would have been more accurate if I weren't ill and under the effects
> : of prescribed narcotics. What's your excuse?
> 
>> Hey, no need to cop an attitude. I really thought you didn't
>> know.
>> My statement was not meant to be taken the way you apparently
>> did,
>> so, I shall not speak at you again. Sorry, very sorry.
>
>Ok Bill. Let's assume that you have just told us the truth here. In that 
>case, please note that you have corrected my 
>misstatement/misunderstanding about 200 vs 400 nanosecond rating of the 
>chips. So, why did you not saying anything about what I really needed to 
>know? Is/Are (I'm still suffering from diminished mental ability due to 
>illness and meds) 200 nanosecond chips fast enough for the IIgs?

 Maybe you need to study a bit.  The speed rating of the chips is the maximum
access rate. The 200ns chips can be accessed or addressed at 200ns intervals,
or every 200ns. 200ns is twice as fast as 400ns.  The ns is nano Seconds, which
is a measurement of time.  100ns is 4 times as fast as 400ns.  So if you have
determined that 400ns chips are fast enough, then the 200ns chips are overkill,
since they can be accessed twice as fast as you need.

  Let's say they made a 600ns chip, and you tried to put it in your IIgs.  It
wouldn't work, because the CPU would be trying to access the chip every 400ns,
and the chip can only be accessed every 600ns.  It's can't handle it.

  Obviously, they never made a 400mns chip, and the majority of the ones you'll
find are 70 or 80ns chips.  

  It's late, and I want to get up early and ride my motorcycle out to the Hill
Country tomorrow.

Raymond