M306H7MG-XXXFP Datasheet, PDF (125/329 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER with DATA ACQUISITION CONTROLLER

M306H7MG-XXXFP/MC-XXXFP/FGFP
10. SERIAL I/O
10.4.8 Initialization of Transmission/Reception
If a start condition is detected while the STAC bit = 1 (UARTi initialization enabled), the serial I/O operates as
described below.
The transmit shift register is initialized, and the content of the UiTB register is transferred to the transmit shift
register. In this way, the serial I/O starts sending data synchronously with the next clock pulse applied.
However, the UARTi output value does not change state and remains the same as when a start condition was
detected until the first bit of data is output synchronously with the input clock.
The receive shift register is initialized, and the serial I/O starts receiving data synchronously with the next clock
pulse applied.
The SWC bit is set to “1” (SCL wait output enabled). Consequently, the SCLi pin is pulled low at the falling
edge of the ninth clock pulse.
Note that when UARTi transmission/reception is started using this function, the TI does not change state. Note
also that when using this function, the selected transfer clock should be an external clock.
Rev.2.10 Oct 25, 2006 Page 125 of 326
REJ03B0152-0210