45.7.2 USART Control Register (SPI_MODE)
This configuration is relevant only if USART_MODE = 0xE or 0xF in the USART Mode Register.
| Name: | US_CR (SPI_MODE) |
| Offset: | 0x0000 |
| Reset: | – |
| Property: | Write-only |
| Bit | 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | |
| Access | |||||||||
| Reset |
| Bit | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | |
| RCS | FCS | ||||||||
| Access | W | W | |||||||
| Reset | – | – |
| Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
| RSTSTA | |||||||||
| Access | W | ||||||||
| Reset | – |
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| TXDIS | TXEN | RXDIS | RXEN | RSTTX | RSTRX | ||||
| Access | W | W | W | W | W | W | |||
| Reset | – | – | – | – | – | – |
Bit 19 – RCS Release SPI Chip Select
Applicable if USART operates in SPI Host mode (USART_MODE = 0xE):
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Releases the Client Select Line NSS (RTS pin). |
Bit 18 – FCS Force SPI Chip Select
Applicable if USART operates in SPI Host mode (USART_MODE = 0xE):
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Forces the Client Select Line NSS (RTS pin) to 0, even if USART is not transmitting, in order to address SPI Client devices supporting the CSAAT mode (Chip Select Active After Transfer). |
Bit 8 – RSTSTA Reset Status Bits
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Resets the status bits OVRE, UNRE in US_CSR. |
Bit 7 – TXDIS Transmitter Disable
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Disables the transmitter. |
Bit 6 – TXEN Transmitter Enable
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Enables the transmitter if TXDIS is 0. |
Bit 5 – RXDIS Receiver Disable
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Disables the receiver. |
Bit 4 – RXEN Receiver Enable
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Enables the receiver, if RXDIS is 0. |
Bit 3 – RSTTX Reset Transmitter
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Resets the transmitter. |
Bit 2 – RSTRX Reset Receiver
| Value | Description |
|---|---|
| 0 | No effect. |
| 1 | Resets the receiver. |