SH7011 Datasheet, PDF (265/292 Pages) Renesas Technology Corp – CMOS single-chip microprocessors

15.3.2 Port E Data Register (PEDR)
PEDR is a 16-bit read/write register that stores data for port E. Table 15.5 shows the
correspondence between PEDR bits and port E pins. When the pins are used as ordinary outputs,
they will output whatever value is written in the PEDR; when PEDR is read, the register value will
be read 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 PEDR is read. When a value is written to PEDR, that
value can be written into PEDR, but it will not affect the pin status. Table 15.4 shows the
read/write operations of the port E data register.
PEDR is initialized by a power-on reset. However, PEDR is not initialized for a sleep mode, so the
previous data is retained.
Bit: 15
14
13
12
11
10
9
8
— PE14DR PE13DR PE12DR —
—
—
—
Initial value: 0
0
0
0
0
0
0
0
R/W: R
R/W R/W R/W
R
R
R
R
Bit: 7
6
5
4
3
2
1
0
PE7DR PE6DR PE5DR PE4DR — PE2DR — PE0DR
Initial value: 0
0
0
0
0
0
0
0
R/W: R/W R/W R/W R/W
R
R/W
R
R/W
Table 15.4 Read/Write Operation of the Port E Data Register (PEDR)
PEIOR
0
1
Pin Status
Read
Ordinary input Pin status
Other function Pin status
Ordinary output PEDR value
Other function PEDR value
Write
Can write to PEDR, but it has no effect on pin status
Can write to PEDR, but it has no effect on pin status
Value written is output by pin
Can write to PEDR, but it has no effect on pin status
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