HD6413002 Datasheet, PDF (260/700 Pages) Renesas Technology Corp – High-performance single-chip microcontroller

Port 4
D₇ (input/output)
D₆ (input/output)
D₅ (input/output)
D₄ (input/output)
D₃ (input/output)
D₂ (input/output)
D₁ (input/output)
D₀ (input/output)
Figure 9-3 Pin Functions in 16-Bit Bus Mode (Port 4)
9.2.4 Input Pull-Up Transistors
Port 4 has built-in MOS input pull-up transistors that can be controlled by software. These input
pull-up transistors can be used in 8-bit bus mode. They can be turned on and off individually.
In 8-bit bus mode, when a P4PCR bit is set to 1 and the corresponding P4DDR bit is cleared to 0,
the input pull-up transistor is turned on.
The input pull-up transistors are turned off by a reset and in hardware standby mode. In software
standby mode they retain their previous state.
Table 9-3 summarizes the states of the input pull-ups in the 8-bit and 16-bit bus modes.
Table 9-3 Input Pull-Up Transistor States (Port 4)
Mode
Reset
Hardware
Standby Mode
Software
Standby Mode
Other Modes
8-bit bus mode
Off
Off
On/off
On/off
16-bit bus mode
Off
Off
Legend
Off: The input pull-up transistor is always off.
On/off: The input pull-up transistor is on if P4PCR = 1 and P4DDR = 0. Otherwise, it is off.
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