HD6435348R Hitachi Semiconductor, HD6435348R Datasheet - Page 179

• Manufacturer Part Number: HD6435348R
• Description: Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

Pin Functions in Modes 2 and 4: In modes 2 and 4, (expanded modes in which the on-chip
ROM is used), software can select whether to use port 5 for general-purpose input, or for output
of bits A
If a bit in P5DDR is set to 1, the corresponding pin is used for address output. If the bit is cleared
to 0, the pin is used for input. A reset clears all P5DDR bits to 0, so before the address bus is
used, all necessary bits in P5DDR must be set to 1.
Figure 9-13 shows the pin functions in modes 2 and 4.
Pin Functions in Single-Chip Mode: In the single-chip mode (mode 7), each of the port 5 pins
can be designated as an input pin or an output pin, as indicated in figure 9-14, by setting the
corresponding bit in P5DDR to 1 for output or clearing it to 0 for input.
15
– A
Port
Port
5
5
8
of the address bus.
Figure 9-14 Port 5 Pin Functions in Single-Chip Mode
Figure 9-13 Port 5 Pin Functions in Modes 2 and 4
When P5DDR
Bit is Set to “1”
A
A
A
A
A
A
A
A
P5
P5
P5
P5
P5
P5
P5
P5
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
(output)
(output)
(output)
(output)
(output)
(output)
(output)
(output)
(input/output)
(input/output)
(input/output)
(input/output)
(input/output)
(input/output)
(input/output)
(input/output)
162
When P5DDR Bit
is Cleared to “0”
P5
P5
P5
P5
P5
P5
P5
P5
7
6
5
4
3
2
1
0
(input)
(input)
(input)
(input)
(input)
(input)
(input)
(input)