Cheetah Cub board

From: Roger Merchberger <zmerch_at_30below.com>
Date: Wed Jun 9 14:59:19 2004

Rumor has it that Doc Shipley may have mentioned these words:
>Steve Thatcher wrote:
>
>>hmmm, I thought there were four rows of 18 chips. That sounds like 8
>>banks of 256K which seems
>>like 2meg to me... unless I got something wrong
>
> No, I guess I got it wrong. I thought you meant 256K per chip, or 4MB
> per bank (16 * 256K plus 2 * 256K for parity).
>
> So are these 256K per bank, or 256K per chip?

Yes. ;-)

-=-=-=-=-=-=-=-

They're 256K*bit* chips, so it takes 8 (or 9 if you use parity) chips to
make 256K*byte*s of storage. So, just saying "256K" isn't quite enough
information to enumerate exactly what's meant...

> IOW, if they turn out to be compatible and I install 16 of them on the
> Amiga A2091, will that be a 2MB or 0.25MB upgrade?

Neither -- 16 would give you a 0.5MegaByte upgrade. 8 would give you 0.25MB.[1]

> Heh. I'd rather stick my face in the mud.... [family joke]

My brain's *way* too frelled up right now to get into that...
Vioxx & Beer -- *bad* combination. My Doc (not you, Doc ;-) says I gotta
keep taking the Vioxx, so no beer. :-((~~

HTH,
Roger "Merch" Merchberger

[1] I figured I shouldn't mention until later that the upgrade you mention
would give you 256K*words* of memory, as the Amiga's a 16-bit machine... 4
bits = nybble, 8 bits = byte, CPU data width = word. (The last part is a
bit simplistic, but...)

--
Roger "Merch" Merchberger   | "Profile, don't speculate."
sysadmin, Iceberg Computers |     Daniel J. Bernstein
zmerch_at_30below.com          |
Received on Wed Jun 09 2004 - 14:59:19 BST

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