HD6433937 Datasheet, PDF (163/521 Pages) Hitachi Semiconductor – Hardware Manual

Bit 2: P3₂/RESO pin function switch (RESO)
This bit selects whether pin P3₂/RESO is used as P3₂ or as RESO.
Bit 2
RESO
0
1
Description
Functions as P3₂ I/O pin
Functions as RESO output pin
Bit 1: P3₁/UD pin function switch (UD)
This bit selects whether pin P3₁/UD is used as P3₁ or as UD.
Bit 1
UD
0
1
Description
Functions as P3₁ I/O pin
Functions as UD input pin
(initial value)
(initial value)
8.4.3 Pin Functions
Table 8-9 shows the port 3 pin functions.
Table 8-9 Port 3 Pin Functions
Pin
P3₇, P3₆, P3₀
P3₅/TXD₃₁
P3₄/RXD₃₁
Pin Functions and Selection Method
The pin function depends on bit PCR3n in PCR3.
PCR3_n
Pin function
0
P3_n input pin
(n=7, 6, 0)
1
P3_n output pin
The pin function depends on bit TE in SCR31, bit SPC31 in SPCR, and bit
PCR3₅ in PCR3.
SPC31
0
1
TE
0
1
PCR3₅
Pin function
0
P3₅ input pin
1
P3₅output pin
*
TXD₃₁ output pin
The pin function depends on bit RE in SCR31 and bit PCR3₄ in PCR3.
RE
0
1
PCR3₄
Pin function
0
P3₄ input pin
1
P3₄ output pin
*
RXD₃₁ input pin
151