HD6435348R Hitachi Semiconductor, HD6435348R Datasheet - Page 187

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

9.7.3 Pin Functions in Each Mode
The usage of port 6 depends on the MCU operating mode. Separate descriptions are given below.
Pin Functions in Mode 3: In mode 3 (the expanded maximum mode in which the on-chip ROM
is not used), P6DDR is automatically set for output, and the pins of port 6 carry the page address
bits (A
Pin Functions in Mode 4: In mode 4, (the expanded maximum mode in which the on-chip ROM
is used), software can select whether to use port 6 for general-purpose input, IRQ
or output of page address bits.
If a bit in P6DDR is set to 1, the corresponding pin is used for page address output. If the P6DDR
bit is cleared to 0 and the corresponding IRQnE bit is cleared to 0, the pin is used for general-
purpose input. If the P6DDR bit is cleared to 0 and the corresponding IRQnE bit is set to 1, the
pin is used for IRQ
function, so when the address bus is used, all necessary bits in P6DDR must first be set to 1.
Figure 9-17 shows the pin functions in mode 4.
Pin Functions in Single-Chip Mode and Expanded Minimum Modes: In the single-chip mode
(mode 7) and expanded minimum modes (modes 1 and 2), the port 6 pins can be designated
individually as input or output pins.
Port 6 can be used for general-purpose input/output, IRQ input, or PWM output, depending on the
combination of settings of the IRQE and P6PWME bits in system control register 2 and the OE
19
– A
16
Port
) of the address bus. Figure 9-16 shows the pin functions for mode 3.
6
2
to IRQ
Port
Figure 9-16 Port 6 Pin Functions in Mode 3
Figure 9-17 Port 6 Pin Functions in Mode 4
6
5
input. A reset initializes these pins to the general-purpose input
When P6DDR Bit
is Set to 1
A
A
A
A
19
18
17
16
(output)
(output)
(output)
(output)
A
A
A
A
19
18
17
16
(output)
(output)
(output)
(output)
170
When P6DDR Bit is Cleared to 0
P6
P6
P6
P6
IRQnE = 0
3
2
1
0
(input)
(input)
(input)
(input)
IRQnE = 1
IRQ
IRQ
IRQ
IRQ
5
4
3
2
2
to IRQ
5
input,