SH7011 Datasheet, PDF (263/292 Pages) Renesas Technology Corp – CMOS single-chip microprocessors

15.2.2 Port A Data Register H (PADRH)
PADRH is a 16-bit read/write register that stores data for port A. The bits PA19DR–PA18DR
correspond to the PA19 pin and PA18 pin. When the pins are used as ordinary outputs, they will
output whatever value is written in the PADRH; when PADRH is read, the register value will be
output regardless of the pin status. When the pins are used as ordinary inputs, the pin status rather
than the register value is read directly when PADRH is read. When a value is written to PADRH,
that value can be written into PADRH, but it will not affect the pin status. Table 15.2 shows the
read/write operations of the port A data register.
PADRH is initialized by an external power-on reset. However, PADRH is not initialized in sleep
mode, so the previous data is maintained.
Bit: 15
14
13
12
11
10
9
8
—
—
—
—
—
—
—
—
Initial value: 0
0
0
0
0
0
0
0
R/W: R
R
R
R
R
R
R
R
Bit: 7
6
5
4
3
2
1
0
—
—
—
— PA19DR PA18DR —
—
Initial value: 0
0
0
0
0
0
0
0
R/W: R
R
R
R
R/W R/W
R
R
Table 15.2 Port A Data Register (PADR) Read/Write Operations
PAIOR
0
1
Pin Function
Input
Output
Read
Pin status
PADR value
Write
Can write to PADR, but it has no effect on pin
status
Value written is output by pin
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