FUNCTIONAL
DESCRIPTION
These
cards are 24-bit parallel, digital input/output cards designed
for use in PCI-Bus computers. The difference between the
models is that I/O connections to PCI-DIO24D are via a standard
37-pin D-sub connector while I/O connections to PCI-DIO24H
are via a 50-pin connector. The cards are 4.80 inches long
(122 mm) and may be installed in any 5V PCI-bus slot in
IBM and compatible personal computers.
These
cards contain a type 8255-5 Programmable Peripheral Interface
(PPI) chip. They can be programmed to accept inputs or to
provide outputs on three 8-bit ports: designated Ports A,
B, and C. Port C can be further divided into two 4-bit nibbles.
Each
I/O line is buffered by a type 74LS245 tristate buffer transceiver
capable of sourcing 15 mA. or sinking 24 mA. (64 mA. on
request (74F245)). The buffers are configured under program
control for input or output use according to direction control
signals from the control register inside the PPI. Pull-ups
(to +5 VDC) on the card assure that there are no erroneous
outputs at power-up until the card is initialized by system
software. Further, jumpers on the card provide a choice
to either permanently enable the buffers or to tri-state
them under program control.
Input/Output
wiring connections for the PCI-DIO24D are via a 37-pin D-sub
connector on the card mounting bracket. Either a 37-pin
D-sub solder cup mating connector or an insulation-displacement
ribbon cable can be used for I/O connections. Fused +5 VDC
power is available at the I/O connector. A resettable on-board
fuse is rated at 0.5A and can be reset by cycling computer
power.
Input/Output
wiring connections for PCI-DIO24H are via a 50-pin connector
on the card mounting bracket. Insulation displacement ribbon
cables can be used for I/O connections to termination panels
such as Chassis Plans model STA-50 Screw Terminal card. The pin
connections are also compatible with Chassis Plans A24A , OPTO22,
Gordos, Potter & Brumfield, etc opto-isolated module mounting
racks. If needed for external circuits, fused +5VDC power
is available at the I/O connector. The resettable 0.5A fuse
can be reset by cycling computer power.
COUNTER/TIMERS
Optionally
you can have one, two, or three 48-bit down counters configured
as Event Counters. (See the Block Diagram which shows one
48-bit counter.) and can also be used as a Frequency source.
To designate that you wish these counters, add -S01, -S02,
and -S03 respectively to the model number. For example,
a 24-bit digital input/output card with a 50-pin connector
and one 48-bit counter is model PCI-DIO24H-S01.
