OK folks - quick update on the logic analyser project...

  1) I've got the triggering and bus interface Vlog code done, checked and
tested. That just leaves the clock divider and acquisition control left to
do.

  2) I can't get any 10ns RAMs, and even if I did I doubt they'd actually be
able to write at the full 100MHz without thoroughly violating the data hold
time specs.

  3) I can, however, get 15ns RAMs that would easily be able to handle a
50MHz (or probably a bit faster) sample clock. They're Cypress CY7C1021s, in
case anyone feels like pulling the datasheet and reading it. 44-pin SOJ,
1.27mm pin pitch (no smaller than a SOIC). DigiKey have got the 10ns version,
which should be OK as a substitute. No guarantees on sample rate, but I want
20MHz as a bare minimum, and I'm actually aiming for 50MHz.

  4) I've got the equipment to do double-sided PCB manufacture, but I don't
have anything to do plated holes with. If anyone wants to donate a few
Multicore Copperset bail-bars and a 0.9mm pencil, I'm not going to stop them
:). I've already got a modified centre-punch, 0.85mm drill bit and a small
anvil, so that's most of the tools covered.

  5) Construction is going to be mostly SMD but with some through hole parts
(connectors mostly). I hate drilling holes in PCBs. Offboard connections are
going to be USB, 9-12V power and 16-bit bus input. I estimate the final board
size to be somewhere around Eurocard size, though with a bit of luck (and a
lot of SMDs) I might be able to get it down to half-Eurocard.

  6) Schematics will be released as-and-when. I want to get the basic
hardware design stabilised before I release anything. Thankfully the CPLD
should allow me to fix most Silly Bugs (tm) without cutting and rerouting
tracks.

  7) I'm using a PIC18F4550, mainly because that's the only USB PIC I've got
in my junk box.

Thanks.
-- 
Phil.                         | Kitsune: Acorn RiscPC SA202 64M+6G ViewFinder
philpem@dsl.pipex.com         | Cheetah: Athlon64 3200+ A8VDeluxeV2 512M+100G
http://www.philpem.me.uk/     | Tiger: Toshiba SatPro4600 Celeron700 256M+40G
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