Renesas R-IN32M3 Series User Manual page 99

R-IN32M3-CL User's Manual
7.5 Buffer Switching Registers (DRCTL)
For some port pins, the driving ability and the connection or disconnection of a pull-up or pull-down resistor is
programmable.
Set up the DRCTL registers during initialization after release from the reset state. After that, change the setting of a given
DRCTL register only while the buffer functions for the corresponding pins are not in use. For example, change the
setting while only internal access is proceeding.
The settings of the DRCTL registers are effective for output pins regardless of their operating mode (port mode, or
control mode, in which a multiplexed function is used).
•
Access
Cautions 1. These registers are only writable after protection has been released by a special
sequence of writing to the system protection command register (SYSPCMD). For how to
release protection, see the description of the system protection command register
(SYSPCMD). No special sequence is required for reading the register.
2. Take special care with pins in the high-impedance state, since changing the settings for
the pull-up and pull-down resistors will affect levels on the pins.
R18UZ0005EJ0400
Dec. 28, 2018
These registers can be read and written in 32-bit or 16-bit units.
7. Port Functions
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