Hitachi H8S/2670, Reference Manual

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Port 1 Register (PORT1)
Bit 7 6 5 4 3 2 1 0
P17 P16 P15 P14 P13 P12 P11 P10
Initial value — * — * — * — * — * — * — * — *
Read/Write R R R R R R R R
Note: * Determined by the state of pins P17 to P10.
PORT1 is an 8-bit read-only register that shows the pin states. PORT1 cannot be written to;
writing of output data for the port 1 pins (P17 to P10) must always be performed on P1DR.
If a port 1 read is performed while P1DDR bits are set to 1, the P1DR values are read. If a port 1
read is performed while P1DDR bits are cleared to 0, the pin states are read.
After a reset and in hardware standby mode, PORT1 contents are determined by the pin states, as
P1DDR and P1DR are initialized. PORT1 retains its prior state in software standby mode.
5.2.3 Pin Functions
Port 1 pins also function as PPG output pins (PO15 to PO8), TPU I/O pins (TCLKA, TCLKB,
TCLKC, TCLKD, TIOCA0, TIOCB0, TIOCC0, TIOCD0, TIOCA1, TIOCB1, TIOCA2, and
TIOCB2), and EXDMAC output pins (
EDRAK2
and
EDRAK3
). Port 1 pin functions are shown
in table 5.3.