HP 9020 CE Handbook page 73

7 -6 9020
Peripherals
To configure the GPIO card:
1. Install jumpers in WI, W2, and W3, according to whether 5-volt or 12-volt logic levels are to
be used.
2. Set the card's switches for proper operation.
3. If necessary, increase the delays on the card as follows:
Two one-shots (EI5) on the GPIO card generate the write delay and the internal handshake
delay. The write delay one-shot provides approximately 100 nsec for the output data to
settle. When extra-long cables are used. or when the peripheral device requires additional
settling time for the data. the delay can be increased by adding a capacitor between pins 1
and 4 of the socket at E16.
The formula for selecting the capacitor value is:
C
=
(T-I00)/1.5
where
C
=
additional capacitance (in pf)
T
=
total time delay required in nsec
The internal delay one-shot provides a delay of approximately 3 usec between the assertion
of PCNTL and the assertion of FLAG. The delay can be increased by adding a capacitor
between pins 5 and 8 of the socket at E16.
The formula for the value of the capacitor is:
C
=
(T-3000)/3
where
C = additional capacitance (in pf)
T
=
total time delay required (in nsec)
27112A
GPIO
Interface
Std. Cable. 5m
Pin & Socket
Connector
(27112-60006
or
27112-63002)
(Included)
5O-Pln Female
Connector
HP 27112A GPIO Interface Cabling
97060A
3xBNC. 2m (Included With 97060A)
Hp·IB Cable. Not Included
Unterminated
Color
Monitor
Such As
HP 13279B
To 9111 A Tablet
Interconnecting the HP 97060A Graphics Processor
09020·90035. rev.T85