96 channel port?

[Bob Stephens]

I need to scan a large matrix of points to check for voltage
presence/absence. IITR somebody came out with a "4 8255's on a chip" chip
with basically 96 i/o ports in one package. Extensive Googling came up with
zilch. Does this ring any bells?

TIA


Bob

 

[Dan Major]

I need to scan a large matrix of points to check for voltage
presence/absence. IITR somebody came out with a "4 8255's on a chip"
chip with basically 96 i/o ports in one package. Extensive Googling
came up with zilch. Does this ring any bells?

Keithly/Metrabyte used to make one, and ISA board. Here's a cheaper knock-
off, again, and ISA board:
http://www.measurementcomputing.com/cbicatalog/cbiproduct.asp?dept_id=216
&pf%5Fid=219&mscssid=594CHHSNF9DP8P5AHAH6BJLCME2QB358

(if the URL doesn't wrap, go to the measurementcomputing home page, and
follow the links to the digital IO then ISA Parallel. They have boards
with up to 192 inputs/outputs)

 

[Bob Stephens]

Keithly/Metrabyte used to make one, and ISA board. Here's a cheaper knock-
off, again, and ISA board:
http://www.measurementcomputing.com/cbicatalog/cbiproduct.asp?dept_id=216
&pf%5Fid=219&mscssid=594CHHSNF9DP8P5AHAH6BJLCME2QB358

(if the URL doesn't wrap, go to the measurementcomputing home page, and
follow the links to the digital IO then ISA Parallel. They have boards
with up to 192 inputs/outputs)

Thanks Dan, but I'm looking for an IC to incorporate on one of our boards.
I've used the DIO/CIO ISA boards for years on PC based projects. They all
still seem to use 8255's or clones though. I thought someone had come out
with a higher channel count part.


Bob

 

[Nico Coesel]

In all honesty, look at using a CPLD. The basic functionality needed will
fit in the smallest gate count devices, so it just becomes a matter of
finding one with enough I/O pins. I suspect the higher channel count
devices do use this approach.

A Xilinx SpartanII 100k gate device could include a PCI interface as
well and has the advantage that it can have any pin as input or output
while being 5V tolerant.

 

[Roger Hamlett]

Thanks Dan, but I'm looking for an IC to incorporate on one of our boards.
I've used the DIO/CIO ISA boards for years on PC based projects. They all
still seem to use 8255's or clones though. I thought someone had come out
with a higher channel count part.

In all honesty, look at using a CPLD. The basic functionality needed will
fit in the smallest gate count devices, so it just becomes a matter of
finding one with enough I/O pins. I suspect the higher channel count
devices do use this approach.

Best Wishes

 

[Ken Smith]

[/QUOTE]

How about a CPLD or a micro with many ports?