40.8.1 SPI Control Register
This register can only be written if the WPCREN bit is cleared in the SPI Write Protection Mode Register.
Name: | SPI_CR |
Offset: | 0x00 |
Reset: | – |
Property: | Write-only |
Bit | 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | |
LASTXFER | |||||||||
Access | W | ||||||||
Reset | – |
Bit | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | |
Access | |||||||||
Reset |
Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
REQCLR | |||||||||
Access | W | ||||||||
Reset | – |
Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
SWRST | SPIDIS | SPIEN | |||||||
Access | W | W | W | ||||||
Reset | – | – | – |
Bit 24 – LASTXFER Last Transfer
Refer to section Peripheral Selection for more details.
Value | Description |
---|---|
0 | No effect. |
1 | The current NPCS is deasserted after the character written in TD has been transferred. When SPI_CSRx.CSAAT is set, the communication with the current serial peripheral can be closed by raising the corresponding NPCS line as soon as TD transfer is completed. |
Bit 12 – REQCLR Request to Clear the Comparison Trigger
0: No effect.
1: Restarts the comparison trigger to enable SPI_RDR loading.
Bit 7 – SWRST SPI Software Reset
The SPI is in Client mode after software reset.
Value | Description |
---|---|
0 | No effect. |
1 | Reset the SPI. A software-triggered hardware reset of the SPI interface is performed. |
Bit 1 – SPIDIS SPI Disable
Disable SPI operation after current transmission is over.
If a transfer is in progress when SPIDIS is set, the SPI completes the transmission of the shifter register and does not start any new transfer, even if SPI_THR is loaded.
If both SPIEN and SPIDIS are equal to one when SPI_CR is written, the SPI is disabled.
Value | Description |
---|---|
0 | No effect. |
1 | Disables the SPI. |
Bit 0 – SPIEN SPI Enable
Value | Description |
---|---|
0 | No effect. |
1 | Enables the SPI to transfer and receive data. |