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 3130292827262524 
        LASTXFER 
Access W 
Reset  
Bit 2322212019181716 
          
Access  
Reset  
Bit 15141312111098 
    REQCLR     
Access W 
Reset  
Bit 76543210 
 SWRST     SPIDISSPIEN 
Access WWW 
Reset  

Bit 24 – LASTXFER Last Transfer

Refer to section Peripheral Selection for more details.

ValueDescription
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.

ValueDescription
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.

ValueDescription
0

No effect.

1

Disables the SPI.

Bit 0 – SPIEN SPI Enable

ValueDescription
0

No effect.

1

Enables the SPI to transfer and receive data.