Datasheet

RL78/L12 CHAPTER 4 PORT FUNCTIONS
R01UH0330EJ0200 Rev.2.00 118
Dec 13, 2013
(2) Setting procedure when using output pins of UART0, CSI00, and CSI01 functions in N-ch open-drain output
mode
In case of UART0: P12
In case of CSI00: P10, P12
In case of CSI01: P15, P17
<1> Using an external resistor, pull up externally the pin to be used to the power supply of the target device
(on-chip pull-up resistor cannot be used).
<2> After reset release, the port mode is the input mode (Hi-Z).
<3> Set the output latch of the corresponding port to 1.
<4> Set the corresponding bit of the POM1 register to 1 to set the N-ch open drain output (V
DD tolerance
Note 1
/EVDD tolerance
Note 2
) mode.
<5> Enable the operation of the serial array unit and set the mode to the UART/CSI mode.
<6> Set the corresponding bit of the PM1 register to the output mode. At this time, the output data is high
level, so the pin is in the Hi-Z state.
Notes 1. For 32-, 44-, 48-, and 52-pin products
2. For 64-pin products