16 Dec
2001
16 Dec
'01
11:51 p.m.
"Peter C. Wallace" wrote:
ajp166 wrote:
A newer chip that can still be found is the WD37C65
that will do 125ns easily. Or you could easily find a d765
off an old board or NOS from JDR.
Do you know of a WD37C65 data sheet on the web?
Allison
I've built enough to enjoy later parts as I'm old enough to want
it done in a lifetime and the older parts meant tons more support
parts and the requisite connections. Of the latter, the fewer the
better for both buildability and reliability.
Hmm what ever happened to sockets and
repairable stuff.
I guess you are not using Xilinx, but one thing
I've noticed lately is the
appearance of large, serial flash EEPROMs. We are using one on them in a
new Xilinx design. The SST part is a 1 Mb chip (128KBytes) 8 pin SOP
package = $1.35. So instead of Xilinx's $4.40 OTP chip we use a 8 pin PIC
and the serial EEPROM for a total of $2.29 and get re-programmability...
A good solution but this is a one-shot project so price is not a major
problem
here. One possible option is going to quick-logic's FPGA's and the web
design
setup. I think you can get a free FPGA programed under that system for
R&D.
At the time I got my FPGA kit they did not have a Xilinx fpga kit the
size
I needed ( 800? Logic blocks ) or free Xilinx software.
--
Ben Franchuk --- Pre-historic Cpu's --
www.jetnet.ab.ca/users/bfranchuk/index.html