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PIO- STATUS SIGNALS (cont.)
PIOS - If any of the signals IDA or
INPUT STROBE JUMPER AREA
The INPUT STROBE JUMPER AREA allows the
User to select one of five types of input
strobe- signals.
port 1 correspond to J2 and J4 for PIO port
2 .
If no jumper is placed at J3 (J4 for PIO
port 2), the data lines will be monitored but
not latched.
on J3 (J4) if an external pulse is used as the
input strobe.
if edge triggering is to be used.
If J1 (J2 for PIO 2) is present, a positive
strobe is selected.
negative strobe is selected.
V. 2 . . . . EXTERNAL INTERFACE CONNECTIONS
Table 10 lists the signals to be used
in interfacing the two parallel I/O ports
with external devices.
PIO CONTROL SIGNALS
The PIO Output Ports each have 3 Control
Lines.
ODR -
ODR goes high, PIOS will go
high.
The signal which
occurred may be determined
by using the Control Output
Port bits 6 and 7 as shown
in Table 4.
Note that J1 and J3 for PIO
A jumper is placed from A to C
A jumper is placed from B to C
If J1 (J2) is omitted, a
These are defined as follows:
an Output Data Ready Line for each
port, to indicate to the processor
when the output device and thus the
output port is ready to receive data.
ODR may be monitored using Interrupts
or the Control Input Port.
can be used as a positive data strebe
for the external output device.
User Guide
This signal
2 - 2 5
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