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μPD780948, μPD78F0948, μPD780949, μPD78F0949
2.3.6 P50 to P57 (Port 5)
These are 8-bit input/output ports. Besides serving as input/output ports, they function as an address
bus and LCD controller/driver.
The following operating modes can be specified bit-wise.
(1) Port mode
These ports function as 8-bit input/output ports. They can be specified bit-wise as input/output ports
with port mode register 5.
(2) Control mode
These ports function as high-order address bus pins (A8 to A15) in external memory expansion mode
or as segment signal ouput pins (S32 to S39) of LCD controller/driver output.
2.3.7 P64, P65 and P67 (Port 6)
These are 3-bit input/output ports. Besides serving as input/output ports, they are used for control in
external memory expansion mode.
The following operating modes can be specified bit-wise.
(1) Port mode
These ports function as 3-bit input/output ports. They can be specified bit-wise as input or output
ports with port mode register 6.
(2) Control mode
These ports function as control signal output pins (RD, WR, ASTB) in external memory expansion
mode, therefore a pin has to be used as a control signal output.
2.3.8 P70 to P77 (Port 7)
This is a 8-bit input/output port. In addition to its use as an input/output port, it also segment sognal
output functions of the LCD controller/driver.
The following operating modes can be specified bit-wise.
(1) Port mode
Port 7 functions as a 8-bit input/output port. Bit-wise specification as an input port or output port
is possible by means of port mode register 7. When used as input ports, pull-up resistors can be
connected by defining the pull-up resistor option register 7.
(2) Control mode
Port 7 functions as segment signal output pins (S24 to S31) of LCD controller/driver.