HD6417021 Hitachi Semiconductor, HD6417021 Datasheet - Page 429

• Manufacturer Part Number: HD6417021
• Description: SuperH RISC engine
• Manufacturer: Hitachi Semiconductor

15.3.2
PBDR is a 16-bit read/write register that stores data for port B. The bits PB15DR–PB0DR
correspond to the PB15/TP15/IRQ7–PB0/TP0/TIOCA2 pins. When the pins are used as ordinary
outputs, they will output whatever value is written in the PBDR; when PBDR is read, the register
value will be output regardless of the pin status. When the pins are used as ordinary inputs, the pin
status rather than the register value is read directly when PBDR is read. When a value is written to
PBDR, that value can be written into PBDR, but it will not affect the pin status. When the pin
function is set to timing pattern output and the TPC output is enabled by the TPC next data enable
register (NDER), no value can be written to PBDR. Table 15.4 shows the read/write operations of
the port B data register.
PBDR is initialized by a power-on reset. However, PBDR is not initialized for a manual reset,
standby mode, or sleep mode.
Table 15.4 Read/Write Operation of the Port B Data Register (PBDR)
PBIOR
0
1
TPn: Timing pattern output
HITACHI 418
Initial value:
Initial value:
Bit name:
Bit name:
Port B Data Register (PBDR)
Pin Status
Input
TPn
Other function
Output
TPn
Other function
R/W:
R/W:
Bit:
Bit:
PB15DR PB14DR PB13DR PB12DR PB11DR PB10DR PB9DR PB8DR
PB7DR PB6DR
R/W
R/W
15
0
7
0
Read
Pin status
Pin status
Pin status
PBDR value
PBDR value
PBDR value
R/W
R/W
14
0
6
0
PB5DR PB4DR
R/W
R/W
13
0
5
0
Write
Can write to PBDR, but it has no effect on pin
status
Disabled
Can write to PBDR, but it has no effect on pin
status
Value written is output by pin
Disabled
Can write to PBDR, but it has no effect on pin
status
R/W
R/W
12
4
0
0
PB3DR
R/W
R/W
11
0
3
0
PB2DR PB1DR
R/W
R/W
10
0
2
0
R/W
R/W
1
0
9
0
PB0DR
R/W
R/W
8
0
0
0