HD6433308 HITACHI [Hitachi Semiconductor], HD6433308 Datasheet - Page 104

• Manufacturer Part Number: HD6433308
• Description: Hitachi Single-Chip MicroComputer
• Manufacturer: HITACHI [Hitachi Semiconductor]

Port 4 Data Register (P4DR)—H’FFB7
Bit
Initial value
Read/Write
P4DR is an 8-bit register containing the data for pins P4
output pins (P4DDR = "1") it reads the value in the P4DR latch, but for input pins (P4DDR = "0"),
it obtains the logic level directly from the pin, bypassing the P4DR latch. This also applies to pins
used for timer input or output.
MOS Pull-Ups: Are available for input pins, including timer input pins, in all modes. Software
can turn the MOS pull-up on by writing a “1” in P4DR, and turn it off by writing a “0.”
Pins P4
input or output, or input of 8-bit timer clock and reset signals. When a pin is used for timer signal
input, its P4DDR bit should normally be cleared to "0;" otherwise the timer will receive the value
in P4DR. If input pull-up is not desired, the P4DR bit should also be cleared to "0."
Pins P4
input or output, or for 8-bit timer output (P4
used for timer output are unaffected by the values in P4DDR and P4DR, and their MOS pull-ups
are automatically turned off.
Reset and Hardware Standby Mode: A reset or entry to the hardware standby mode clears
P4DDR and P4DR to all “0” and makes all pins into input port pins with the MOS pull-ups off.
Software Standby Mode: In the software standby mode, the control registers of the 8-bit and
PWM timers are initialized but P4DDR and P4DR remain in their previous states. All pins become
input or output port pins depending on the setting of P4DDR. Output pins output the values in
P4DR. The MOS pull-ups of input pins are on or off depending on the values in P4DR.
Figures 5-4 and 5-5 show schematic diagrams of port 4.
0
1
, P4
, P4
2
4
, P4
, P4
3
6
R/W
P4
, and P4
, and P4
7
0
7
5
7
R/W
: As indicated in Table 5-8, these pins can be used for general-purpose
: As indicated in Table 5-8, these pins can be used for general-purpose
P4
6
0
6
R/W
P4
5
0
5
1
and P4
R/W
89
P4
4
0
4
4
) or PWM timer output (P4
7
to P4
R/W
P4
3
0
3
0
. When the CPU reads P4DR, for
R/W
P4
2
0
2
R/W
P4
1
0
6
1
and P4
R/W
7
P4
). Pins
0
0
0