CR2 register
ADDM7 | ADDM7:7-bit Address Detection/4-bit Address Detection This bit is for selection between 4-bit address detection or 7-bit address detection. -0: 4-bit address detection -1: 7-bit address detection (in 8-bit data mode) This bit can only be written when the USART is disabled (UE=0) |
STOP | STOP[1:0]: STOP bits These bits are used for programming the stop bits. -00: 1 stop bit -01: 0.5 stop bit. -10: 2 stop bits -11: 1.5 stop bits This bit field can only be written when the USART is disabled (UE=0). |
SWAP | SWAP: Swap TX/RX pins This bit is set and cleared by software. -0: TX/RX pins are used as defined in standard pinout -1: The TX and RX pins functions are swapped. This allows to work in the case of a cross-wired connection to another UART. This bit field can only be written when the USART is disabled (UE=0). |
RXINV | RXINV: RX pin active level inversion This bit is set and cleared by software. -0: RX pin signal works using the standard logic levels (VDD =1/idle, Gnd=0/mark) -1: RX pin signal values are inverted. ((VDD =0/mark, Gnd=1/idle). This allows the use of an external inverter on the RX line. This bit field can only be written when the USART is disabled (UE=0). |
TXINV | TXINV: TX pin active level inversion This bit is set and cleared by software. -0: TX pin signal works using the standard logic levels (VDD =1/idle, Gnd=0/mark) -1: TX pin signal values are inverted. ((VDD =0/mark, Gnd=1/idle). This allows the use of an external inverter on the TX line. This bit field can only be written when the USART is disabled (UE=0). |
DATAINV | DATAINV: Binary data inversion This bit is set and cleared by software. -0: Logical data from the data register are send/received in positive/direct logic. (1=H, 0=L) -1: Logical data from the data register are send/received in negative/inverse logic. (1=L, 0=H). The parity bit is also inverted. This bit field can only be written when the USART is disabled (UE=0). |
MSBFIRST | MSBFIRST: Most significant bit first This bit is set and cleared by software. -0: data is transmitted/received with data bit 0 first, following the start bit. -1: data is transmitted/received with the MSB (bit 7/8) first, following the start bit. This bit field can only be written when the USART is disabled (UE=0). |
ADD | ADD[7:0]: Address of the USART node This bit-field gives the address of the USART node or a character code to be recognized. This is used in multiprocessor communication during Mute mode or Stop mode, for wakeup with 7- bit address mark detection. The MSB of the character sent by the transmitter should be equal to 1. It may also be used for character detection during normal reception, Mute mode inactive (for example, end of block detection in ModBus protocol). In this case, the whole received character (8- bit) is compared to the ADD[7:0] value and CMF flag is set on match. This bit field can only be written when reception is disabled (RE = 0) or the USART is disabled (UE=0) |