R8C32A Datasheet, PDF (358/603 Pages) Renesas Technology Corp – MCU M16C FAMILY / R8C/Tiny SERIES

Under development ^{Preliminary specification}
Specifications in this manual are tentative and subject to change.
R8C/32A Group
22. Serial Interface (UART2)
22.4.2 Measure for Dealing with Communication Errors
If a communication error occurs while transmitting or receiving in UART mode, follow the procedures below:
• Resetting the U2RB register
(1) Set the RE bit in the U2C1 register to 0 (reception disabled).
(2) Set the RE bit in the U2C1 register to 1 (reception enabled).
• Resetting the U2TB register
(1) Set bits SMD2 to SMD0 in the U2MR register to 000b (serial interface disabled).
(2) Reset bits SMD2 to SMD0 in the U2MR register to 001b, 101b, and 110b.
(3) Write 1 to the TE bit in the U2C1 register (transmission enabled), regardless of the TE bit value in the
U2C1 register.
22.4.3 LSB First/MSB First Select Function
As shown in Figure 22.9, use the UFORM bit in the U2C0 register to select the transfer format. This function is
enabled when transfer data is 8 bits long. Figure 22.9 shows the Transfer Format.
(1) UFORM Bit in U2C0 Register = 0 (LSB first)
CLK2
TXD2
ST D0 D1 D2 D3 D4 D5 D6 D7 P SP
RXD2
ST D0 D1 D2 D3 D4 D5 D6 D7 P SP
(2) UFORM Bit in U2C0 Register = 1 (MSB first)
CLK2
TXD2
ST D7 D6 D5 D4 D3 D2 D1 D0 P SP
RXD2
ST D7 D6 D5 D4 D3 D2 D1 D0 P SP
The above applies when:
• CKPOL bit in U2C0 register = 0 (transmit data output at the falling edge and
receive data input at the rising edge of the transfer clock)
• U2LCH bit in U2C1 register = 0 (not inverted)
• STPS bit in U2MR register = 0 (one stop bit)
• PRYE bit in U2MR register = 1 (parity enabled)
ST: Start bit
P: Parity bit
SP: Stop bit
Figure 22.9 Transfer Format
REJ09B0458-0010 Rev.0.10 Apr 01, 2008
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