Renesas M16C/64C User Manual page 494

M16C/64C Group
NCH (Data output select bit) (b5)
TXD2/SDA2 and SCL2 are N-channel open drain outputs. They cannot be set as CMOS outputs.
Nothing is assigned to the NCH bit in the U2C0 register. If necessary, set this bit to 0.
This function is used to set the P-channel transistor of the CMOS output buffer always off, but not to
change pins TXDi/SDAi and SCLi to open drain output completely.
Refer to the electrical characteristics for the input voltage range.
UFORM (Bit order select bit) (b7)
The UFORM bit is enabled when bits SMD2 to SMD0 in the UiMR register are 001b (clock synchronous
serial I/O mode), or 101b (UART mode, 8-bit character data).
Set the UFORM bit to 1 when bits SMD2 to SMD0 are 010b (I
SMD0 are 100b (UART mode, 7-bit character data) or 110b (UART mode, 9-bit character data).
R01UH0092EJ0110 Rev.1.10
Jul 31, 2012
23. Serial Interface UARTi (i = 0 to 2, 5 to 7)
2
C mode), and to 0 when bits SMD2 to
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