Section 8 I/O Ports
Rev. 7.00 Mar 10, 2005 page 196 of 652
REJ09B0042-0700
Port Data Register 1 (PDR1)
Bit 76543210
P1
7
P1
6
* —P1
4
P1
3
———
Initial value 0 0 — 0 0 — — —
Read/Write R/W R/W — R/W R/W — — —
PDR1 is an 8-bit register that stores data for port 1 pins P1
7
, P1
6
*, P1
4
, and P1
3
. If port 1 is read
while PCR1 bits are set to 1, the values stored in PDR1 are read, regardless of the actual pin states.
If port 1 is read while PCR1 bits are cleared to 0, the pin states are read.
Note: * Pin 1
6
and the associated function are not implemented on the H8/38124 Group.
The register is both readable and writeable.
Port Control Register 1 (PCR1)
Bit 76543210
PCR1
7
PCR1
6
* — PCR1
4
PCR1
3
———
Initial value 0 0 — 0 0 — — —
Read/Write W W W W W W W W
PCR1 is an 8-bit register for controlling whether each of the port 1 pins P1
7
, P1
6
*, P1
4
, and P1
3
functions as an input pin or output pin. Setting a PCR1 bit to 1 makes the corresponding pin an
output pin, while clearing the bit to 0 makes the pin an input pin. The settings in PCR1 and in
PDR1 are valid only when the corresponding pin is designated in PMR1 as a general I/O pin.
PCR1 is a write-only register, which is always read as all 1s.
Note: * Pin 1
6
and the associated function are not implemented on the H8/38124 Group.
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