Toshiba TLCS-90 Series Data Book page 178

TOSHIBA
TMP8243P/TMP8243PI
PIN NAMES AND PIN DESCRIPTION
PROG (Input)
Clock Input.
A
high to lo~ transistion onPROG signifies that address a~d
control are available on P20-23, and a lo~ to high transi~ion signifies that
data is available on P20-23.
CS (Input)
Chip Select Input. A high on CS inhibits any change of output or internal
status.
P20-23 (Input/Output, 3-state)
Four (4) bit bi-airectional port contains the address and control bits on a
high to low transition of PROG. During a low to high transition contains the
data for a selected output port if a write oepration, or the data from a
selected port before the low to high transition if a read operation.
P40-43, P50-53, P60-63, P70-73 (Input/Output, 3-state)
Four (4) bit bi-directional I/O ports. May be programmed to be input (during
read), low impedance latched output (after write) or a 3-state (after read).
Data on pins P20-23 may be directly written, ANDed or ORed with previous data.
VCC (Power)
+5 volt supply
GND (Power)
o
volt supply
FUNCTIONAL DESCRIPTION
General Operation
The TMP8243P contains four 4-bit 1/0 ports which serve as an extension of the
on-chip 1/0 and are addressed as ports 4-7. The following operations may be
performed on these ports.
o Transfer accumulator to port
o Transfer port to accumulator
o AND accumulator to port
o OR accumulator to port
MCU48-168