HD6473032F Datasheet, PDF (163/572 Pages) Hitachi Semiconductor – Hitachi Microcomputer

Port 8 Data Register (P8DR): P8DR is an 8-bit readable/writable register that stores data for pins
P8₃ to P8₀.
Bit
7
6
5
4
3
2
1
0
—
—
—
—
P8 ₃
P8 ₂
P8 ₁
P8 ₀
Initial value
1
1
1
0
0
0
0
0
Read/Write
—
—
—
R/W
R/W
R/W
R/W
R/W
Reserved bits
Port 8 data 4 to 0
These bits store data
for port 8 pins
When a bit in P8DDR is set to 1, if port 8 is read the value of the corresponding P8DR bit is
returned directly. When a bit in P8DDR is cleared to 0, if port 8 is read the corresponding pin level
is read.
Bits 7 to 4 are reserved. Bits 7 to 5 cannot be modified and always read 1. Bit 4 can be written and
read, but it cannot be used for port input or output. If bit 4 of P8DDR is read while its value is 1, bit
4 of P8DR is read directly. If bit 4 of P8DDR is read while its value is 0, it always reads 1.
P8DR is initialized to H'E0 by a reset and in hardware standby mode. In software standby mode it
retains its previous setting.
7.8.3 Pin Functions
The port 8 pins are also used for IRQ₃ to IRQ₀. Table 7-12 describes the selection of pin functions.
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