Datasheet

359
32133D–11/2011
UC3D
• CHMODE: Channel Mode
• NBSTOP: Number of Stop Bits
• PAR: Parity Type
• SYNC/CPHA: Synchronous Mode Select or SPI Clock Phase
If USART does not operate in SPI Mode (MODE is … 0xE and 0xF):
SYNC = 0: USART operates in Asynchronous Mode.
SYNC = 1: USART operates in Synchronous Mode.
If USART operates in SPI Mode, CPHA determines which edge of CLK causes data to change and which edge causes data to
be captured. CPHA is used with CPOL to produce the required clock/data relationship between master and slave devices.
CPHA = 0: Data is changed on the leading edge of CLK and captured on the following edge of CLK.
CPHA = 1: Data is captured on the leading edge of CLK and changed on the following edge of CLK.
Table 20-9.
CHMODE Mode Description
0 0 Normal Mode
0 1 Automatic Echo. Receiver input is connected to the TXD pin.
1 0 Local Loopback. Transmitter output is connected to the Receiver input.
1 1 Remote Loopback. RXD pin is internally connected to the TXD pin.
Table 20-10.
NBSTOP Asynchronous (SYNC=0) Synchronous (SYNC=1)
0 0 1 stop bit 1 stop bit
0 1 1.5 stop bits Reserved
1 0 2 stop bits 2 stop bits
1 1 Reserved Reserved
Table 20-11.
PAR Parity Type
000Even parity
001Odd parity
0 1 0 Parity forced to 0 (Space)
0 1 1 Parity forced to 1 (Mark)
10xNo parity
1 1 x Multidrop mode