Renesas Hitachi H8S/2191, Руководство по оборудованию, Страница: 290 / 1065

Rev. 2.0, 11/00, page 263 of 1037
(2) Port Control Register 4 (PCR4)
0
0
1
0
W
2
0
W
3
0
4
0
W
0
W
5
0
7
0
W W W W
6
PCR44 PCR43 PCR42 PCR41 PCR40 PCR47 PCR46 PCR45
Bit :
Initial value :
R/W :
Port control register 4 (PCR4) controls the I/Os of pins P47 to P40 of port 4 in a unit of bit.
When PCR4 is set to 1, the corresponding P47 to P40 pins become output pins, and when it is set
to 0, they become input pins. When the relevant pin is set to a general I/O by PMR4, settings of
PCR4 and PDR4 become valid.
PCR4 is an 8-bit write-only register. When PCR4 is read, 1 is read. When reset, PCR4 is
initialized to H'00.
Bit n
PCR4n Description
0 The P4n pin functions as an input pin (Initial value)
1 The P4n pin functions as an output pin
(n = 7 to 0)
(3) Port Data Register 4 (PDR4)
0
0
1
0
R/W
2
0
R/W
3
0
4
0
R/W
0
R/W
5
0
7
0
R/W R/W R/W R/W
6
PDR44 PDR43 PDR42 PDR41 PDR40 PDR47 PDR46 PDR45
Bit :
Initial value :
R/W :
Port data register 4 (PDR4) stores the data for the pins P47 to P40 of port 4. When PCR4 is 1
(output), the PDR4 values are directly read if port 3 is read. Accordingly, the pin states are not
affected. When PCR4 is 0 (input), the pin states are read if port 4 is read.
PDR4 is an 8-bit read/write enable register. When reset, PDR4 is initialized to H'00.