HD64F3437TF16 Datasheet, PDF (163/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

7.7.4 Input Pull-Up Transistors
Port 6 has built-in programmable input pull-up transistors. The pull-up for each bit can be turned
on and off individually. To turn on an input pull-up, set the corresponding KMPCR bit to 1 and
clear the corresponding P6DDR bit to 0. KMPCR is cleared to H'00 by a reset and in hardware
standby mode, turning all input pull-ups off. In software standby mode, the previous state is
maintained.
Table 7.14 indicates the states of the input pull-up transistors in each operating mode.
Table 7.14 States of Input Pull-Up Transistors (Port 6)
Mode Reset Hardware Standby Software Standby Other Operating Modes
1
Off
Off
On/off
On/off
2
Off
Off
On/off
On/off
3
Off
Off
On/off
On/off
Notes: Off: The input pull-up transistor is always off.
On/off: The input pull-up transistor is on if KMPCR = 1 and P6DDR = 0, but off otherwise.
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