Port 6; Overview; Register Descriptions - Hitachi F-ZTAT H8/3039 Series Hardware Manual

7.6 Port 6

7.6.1 Overview

Port 6 is a 4-bit input/output port that is also used for input and output of bus control signals (WR,
RD, AS, and WAIT).
Figure 7-16 shows the pin configuration of port 6. In modes 1, 3 and 5, the pin functions are WR,
RD, AS, and P6
/WAIT. In modes 6 and 7, port 6 is a generic input/output port.
0
Pins in port 6 can drive one TTL load and a 90-pF capacitive load. They can also drive a
Darlington transistor pair.
Port 6

7.6.2 Register Descriptions

Table 7-8 summarizes the registers of port 6.
Table 7-8 Port 6 Registers
Address* Name
H'FFC9 Port 6 data
direction register
H'FFCB Port 6 data register
Note: * Lower 16 bits of the address.
Port 6 pins Modes 1, 3 and 5
P6 / WR WR
5
P6 / RD RD
4
P6 / AS AS
3
P6 / WAIT P6
0
0
Figure 7-16 Port 6 Pin Configuration
Abbreviation
P6DDR
P6DR
(output)
(output)
(output)
(input/output)/WAIT (input)
Initial Value
R/W Modes 1, 3, and 5
W H'F8
R/W H'80
Modes 6 and 7
P6 (input/output)
5
P6 (input/output)
4
P6 (input/output)
3
P6 (input/output)
0
Modes 6 and 7
H'80
H'80
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