UPD70F3208 Datasheet, PDF (143/757 Pages) NEC – 32-Bit Single-Chip Microcontrollers

CHAPTER 4 PORT FUNCTIONS
(2) Registers
(a) Port 0 register (P0)
The port 0 register (P0) is an 8-bit register that controls pin level read and output level write. This register
can be read/written in 8-bit or 1-bit units.
After Reset: Undefined R/W Address: FFFFF400H
P0
0
P06
P05
P04
P03
P02
P01
P00
P0n
Control of output data (in output mode) (n = 0 to 6)
0 Output 0
1 Output 1
Remark In input mode: When read, port 0 (P0) returns the current pin level.
When written to, the data written to P0 is written. This has no
influence on the input pins.
In output mode: When read, port 0 (P0) returns the P0 value. When written to, the
value is written to P0 and the written value is immediately output.
(b) Port 0 mode register (PM0)
This is an 8-bit register that specifies the input mode/output mode.
This register can be read/written in 8-bit or 1-bit units.
After Reset: FFH R/W Address: FFFFF420H
PM0
1
PM06 PM05 PM04 PM03 PM02 PM01 PM00
PM0n
0
1
Output mode
Input mode
Control of I/O mode
User’s Manual U15862EJ3V0UD
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