358
10.5.3
Pin Functions
The pins of port 7 are multipurpose pins which function as 8-bit timer I/O pins, (TMRI01,
TMCI01, TMRI23, TMCI23, TMO0, TMO1, TMO2, TMO3), DMAC I/O pins (
DREQ0
,
TEND0
,
DREQ1
,
TEND1
), bus control output pins (
CS4
to
CS7
), IIC input pin (SYNCI), SCI I/O pins
(SCK3, RxD3, TxD3) and manual reset input pin (
MRES
). Table 10-8 shows the functions of port
7 pins.
Table 10-8 Port 7 Pin Functions
Pin
Selection Method and Pin Functions
P77/TxD3
Switches as follows according to combinations of SCR TE bit of SCI3, and the
P77DDR bit.
TE
0
1
P77DDR
0
1
—
Pin function
P77 input pin
P77 output pin
TxD3 output pin
P76/RxD3
Switches as follows according to combinations of SCR RE bit of SCI3 and the
P76DDR bit.
RE
0
1
P76DDR
0
1
—
Pin function
P76 input pin
P76 output pin
RxD3 I/O pin
P75/TMO3/
SCK3
Switches as follows according to combinations of SMR C/
A
bit of SCI3, SCR CKE0
and CKE1 bits, TCSR3 OS3 to OS0 bits of the 8-bit timer, and the P75DDR bit.
OS3 to OS0
All 0
Any is 1
CKE1
0
1
—
C/
A
0
1
—
—
CKE0
0
1
—
—
—
P75DDR
0
1
—
—
—
—
Pin function
P75
input pin
P75
output pin
SCK3
output pin
SCK3
output pin
SCK3
input pin
TMO3
Output