Hitachi H8/329 Series Hardware Manual page 95

Reset and Hardware Standby Mode: A reset or entry to the hardware standby mode clears
P3DDR, P3DR, and P3PCR to all "0." All pins are placed in the high-impedance state with the
pull-up transistors off.
Software Standby Mode: In the software standby mode, P3DDR, P3DR, and P3PCR remain in
their previous state. In modes 1 and 2, all pins are placed in the data input (high-impedance) state.
In mode 3, all pins remain in their previous input or output state.
Input Pull-Up Transistors: Port 3 has built-in programmable input pull-up transistors that are
available in mode 3. The pull-up for each bit can be turned on and off individually. To turn on an
input pull-up in mode 3, set the corresponding P3PCR bit to "1" and clear the corresponding
P3DDR bit to "0." P3PCR is cleared to H'00 by a reset and in the hardware standby mode, turning
all input pull-ups off. In software standby mode, the previous state is maintained.
Table 5-10 indicates the states of the input pull-up transistors in each operating mode.
Table 5-10. States of Input Pull-Up Transistors (Port 3)
Mode Reset
1 Off
2 Off
3 Off
Notes: Off: The input pull-up transistor is always off.
On/off: The input pull-up transistor is on if P3PCR = "1" and P3DDR = "0," but off
otherwise.
Figure 5-3 shows a schematic diagram of port 3.
Hardware standby
Off
Off
Off
Software standby
Off
Off
On/off
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Other operating modes
Off
Off
On/off