HD6433308 Datasheet, PDF (121/349 Pages) Hitachi Semiconductor – Hitachi Single-Chip MicroComputer

Pin P80: In modes 1 and 2 (expanded modes), pin P80 is used for E clock output if P80DDR is set
to "1," and for general-purpose input if P80DDR is cleared “0.” It cannot be used for general-
purpose output.
In mode 3 (single-chip mode), when the dual-port RAM is disabled (DPME = "0"), pin P80 can be
used for general-purpose input or output. In the slave mode (DPME = "1"), this pin is used for
register select input (RS0). In slave mode this pin is unaffected by the values in P8DDR and
P8DR, except that software can turn on its MOS pull-up by clearing its data direction bit to "0" and
setting its data bit to "1."
Pin P81: In modes 1 and 2 (expanded modes), pin P81 is used for IOS output if P81DDR is set to
"1," and for general-purpose input if P81DDR is cleared “0.” It cannot be used for general-purpose
output.
In mode 3, when the dual-port RAM is disabled (DPME = "0"), pin P81 can be used for general-
purpose input or output. In the slave mode (DPME = "1"), this pin is used for register select input
(RS1). In slave mode this pin is unaffected by the values in P8DDR and P8DR, except that
software can turn on its MOS pull-up by clearing its data direction bit to "0" and setting its data bit
to "1."
Pins P82 and P83: These pins are available for general-purpose input or output in modes 1 and 2,
and in mode 3 if the dual-port RAM is disabled (DPME = "0").
In the slave mode (mode 3 with DPME = "1"), these pins are used for register select input (RS2 and
RS3). They are unaffected by the bits in P8DDR and P8DR, except that software can turn on their
MOS pull-ups by clearing the P8DDR bit to "0" and setting the P8DR bit to "1."
Pin P84: This pin has the same functions in all modes. It can be used for general-purpose input or
output, for output of clock-synchronized serial transmit data (CTxD), or for IRQ3 input. When
used for CTxD output, this pin is unaffected by the values in P8DDR and P8DR, and its MOS pull-
up is automatically turned off. When this pin is used for IRQ3 input, P84DDR should normally be
cleared to "0," so that the value in P8DR will not generate interrupts.
Pin P85: This pin has the same functions in all modes. It can be used for general-purpose input or
output, for input of clock-synchronized serial receive data (CRxD), or for IRQ4 input. When used
for CRxD input, this pin is unaffected by the values in P8DDR and P8DR, except that software can
turn on its MOS pull-up by clearing its data direction bit to "0" and setting its data bit to "1." When
this pin is used for IRQ4 input, P85DDR should normally be cleared to "0," so that the value in
P8DR will not generate interrupts.
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