HD6433308 HITACHI [Hitachi Semiconductor], HD6433308 Datasheet - Page 119

• Manufacturer Part Number: HD6433308
• Description: Hitachi Single-Chip MicroComputer
• Manufacturer: HITACHI [Hitachi Semiconductor]

5.9 Port 8
Port 8 is a 7-bit input/output port that also provides pins for E clock output, dual-port RAM register
select input, interrupt input, and clock-synchronized serial communication. Table 5-16 lists the pin
functions.
Table 5-16. Port 8 Pin Functions
I/O port
P8
P8
P8
P8
P8
P8
P8
Pins of port 8 can drive a single TTL load and a 30pF capacitive load when they are used as output
pins. They can also drive a Darlington pair. When used as input pins, they have programmable
MOS pull-ups.
Table 5-17 details the port 8 registers.
Table 5-17. Port 8 Registers
Name
Port 8 data direction register P8DDR
Port 8 data register
0
1
2
3
4
5
6
input/output
input/output
input/output
input/output
input/output
input/output
input/output
Expanded modes
E clock output
IOS output
—
—
CTxD output /IRQ
CRxD input /IRQ
CSCK input/output /IRQ
Abbreviation Read/Write Initial value
P8DR
Auxiliary functions
4
3
input
input
5
input
W
R/W
104
Single-chip mode
RS0 input
RS1 input
RS2 input
RS3 input
H’81 (modes 1 and 2)
H’80 (mode 3)
H'80
Address
H’FFBD
H’FFBF