12 Mar
2005
12 Mar
'05
12:02 p.m.
On Sat, 2005-03-12 at 01:20 +0000, Philip Pemberton wrote:
Hmm, just grabbing a random 486 board from the pile here; it's got 8
61256 chips on it which is presumably 256KB in total. I suppose by the
Pentium era the cache was all in the CPU or something though...
In message <1110586962.6194.110.camel at
weka.localdomain>
Jules Richardson <julesrichardsonuk at yahoo.co.uk> wrote:
The Altera ByteBlaster and Xilinx Parallel Download Cables are literally
three-component devices - a DB25 connector, a 74LS244 and an IDC header. Plug
the cable into the target board, apply power, run the downloader, hit
"Program", then wait a few seconds for the fuse data to download.
Forget all I said then - that's nice and easy ;-)
Why not
stuff it all in a CPLD? Maybe create a logic-only version too...
Well personally I prefer logic-only because I know I'll have the parts
here, plus I don't have any sort of programmer for making more exotic
things (ok, so I do have an ancient PAL/EPROM programmer, but without
manuals I've only ever figured out the EPROM side of it :) I still like
the idea of SRAM from old PC motherboards; didn't they
normally have 64 or even 128KBytes? Free then; with other parts costs
it'd probably make the whole thing do-able for a fiver or so (more with
a few frills like a case, PSU etc.)
I've got a TAG RAM here from a Pentium board and it's only 16k. I'm still
trying to find a few more of them... I did have a SCSI card in my RiscPC, but I replaced it
with a 100BaseT LAN
card, seeing as I wasn't using the SCSI (no SCSI devices to use with the
card).
I unearthed about ten Acorn SCSI cards the other day :-)
seeya
J.