STM8S datasheet(275/467 Pages) STMICROELECTRONICS

номер детали	STM8S

подробное описание детали	STM8S Series and STM8AF Series 8-bit microcontrollers

PDF	467 Pages

Scroll/Zoom	100%

производитель	STMICROELECTRONICS [STMicroelectronics]

домашняя страница	http://www.st.com

Logo

275 / 467 page

DocID14587 Rev 14

275/467

RM0016

Serial peripheral interface (SPI)

287

Figure 99. TXE/BSY behavior when transmitting (BDM = 0 and RXLONY = 0).

Case of discontinuous transfers

20.3.6

CRC calculation

A CRC calculator has been implemented for communication reliability. Separate CRC

calculators are implemented for transmitted data and received data. The CRC is calculated

using a programmable polynomial serially on each bit. The CRC is calculated on the

sampling clock edge defined by the CPHA and CPOL bits in the SPI_CR1 register.

CRC calculation is enabled by setting the CRCEN bit in the SPI_CR1 register. This action

resets the CRC registers (SPI_RXCRCR and SPI_TXCRCR). When the CRCNEXT bit in

SPI_CR2 is set, the SPI_TXCRCR value is transmitted at the end of the current byte

transmission.

If a byte is present in the Tx buffer, the CRC value is transmitted only after the transmission

of this byte. During the transmission of CRC, the CRC calculator is switched off and the

The CRCERR flag in the SPI_SR register is set if the value received in the shift register

during the SPI_TXCRCR value transmission does not match the SPI_RXCRCR value.

STM8S датащи(PDF) 275 Page - STMicroelectronics