HD6413308 Hitachi Semiconductor, HD6413308 Datasheet - Page 99

• Manufacturer Part Number: HD6413308
• Description: Hitachi Single-Chip MicroComputer
• Manufacturer: Hitachi Semiconductor

5.4 Port 3
Port 3 is an 8-bit input/output port that also provides the external data bus and dual-port RAM
(master-slave) data bus. The function of port 3 depends on the MCU mode as indicated in table
5-6.
Table 5-6. Functions of Port 3
Mode 1
Data bus
Pins of port 3 can drive a single TTL load and a 90pF capacitive load when they are used as output
P2
n
Mode 2
Data bus
Hardware standby
Figure 5-2. Port 2 Schematic Diagram
Mode 1, or 2
Mode 1 or 2
Mode 3
DPME = "0"
Input/output port
84
Mode 3
WP2D: Write Port 2 DDR
WP2:
RP2:
n = 0 to7
* Set-priority
DPME = "1"
Dual-port RAM data bus
Write Port 2
Read Port 2
Mode 1 Reset
RP2
Q
P2n DR
Q
P2n DDR
S*
WP2D
WP2
Reset
C
C
R
R
D
D
*