Hitachi H8S/2670, Reference Manual

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Port B Data Register (PBDR)
Bit 7 6 5 4 3 2 1 0
PB7DR PB6DR PB5DR PB4DR PB3DR PB2DR PB1DR PB0DR
Initial value 0 0 0 0 0 0 0 0
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
PBDR is an 8-bit readable/writable register that stores output data for the port B pins (PB7 to
PB0).
PBDR is initialized to H'00 by a reset and in hardware standby mode. It retains its prior state in
software standby mode.
Port B Register (PORTB)
Bit 7 6 5 4 3 2 1 0
PB7 PB6 PB5 PB4 PB3 PB2 PB1 PB0
Initial value — * — * — * — * — * — * — * — *
Read/Write R R R R R R R R
Note: * Determined by the state of pins PB7 to PB0.
PORTB is an 8-bit read-only register that shows the pin states. PORTB cannot be written to;
writing of output data for the port B pins (PB7 to PB0) must always be performed on PBDR.
If a port B read is performed while PBDDR bits are set to 1, the PBDR values are read. If a port B
read is performed while PBDDR bits are cleared to 0, the pin states are read.
After a reset and in hardware standby mode, PORTB contents are determined by the pin states, as
PBDDR and PBDR are initialized. PORTB retains its prior state in software standby mode.
Port B MOS Pull-Up Control Register (PBPCR)
Bit 7 6 5 4 3 2 1 0
PB7PCR PB6PCR PB5PCR PB4PCR PB3PCR PB2PCR PB1PCR PB0PCR
Initial value 0 0 0 0 0 0 0 0
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
PBPCR is an 8-bit readable/writable register that controls the MOS input pull-up function
incorporated into port B on a bit-by-bit basis.