Renesas RL78 Series User Manual page 124

RL78/G1D
(2) Setting procedure when using output pins of UART0, UART1, CSI00, and CSI20 functions in N-ch open-drain
output mode
In case of UART0:
In case of UART1:
In case of CSI00:
In case of CSI20:
<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 POM0 and POM1 registers to 1 to set the N-ch open drain output (V
tolerance) 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 PM0 and PM1 registers to the output mode. At this time, the output data
is high level, so the pin is in the Hi-Z state.
(3) Setting procedure when using I/O pins of IIC00 and IIC20 functions with a different potential (1.8 V, 2.5 V, 3 V)
In case of IIC00: P10, P11
In case of IIC20: P14, P15
<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
mode.
<5> Set the corresponding bit of the PIM1 register to 1 to switch to the TTL input buffer. For V
to the DC characteristics when the TTL input buffer is selected.
<6> Enable the operation of the serial array unit and set the mode to the simplified I
<7> Set the corresponding bit of the PM1 register to the output mode (data I/O is possible in the output mode).
At this time, the output data is high level, so the pin is in the Hi-Z state.
R01UH0515EJ0120 Rev.1.20
Dec 16, 2016
P12
P02
P10, P12
P13, P15
CHAPTER 5 PORT FUNCTIONS
IH
2
C mode.
DD
tolerance)
DD
and V , refer
IL
103