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SPI Register Write

Write data to registers of SPI peripheral devices

  • SPI Register Write block

Libraries:
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32F746G-Discovery
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32F769I-Discovery
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32L475VG-Discovery (B-L475E-IOT01A)
Simulink Coder Support Package for STMicroelectronics Nucleo Boards / Common

Description

The SPI Register Write block writes the data to registers of a peripheral devices over the Serial Peripheral Interface (SPI) interface. Using this block, you can access an SPI device to measure quantities such as temperature, pressure or to support EEPROM.

For more information on SPI communication, see Support SPI Communication.

Ports

Input

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The port accepts the serial data out (SDO) to write to the registers of a peripheral devices over the SPI interface.

Data Types: int8 | uint8 | int16 | uint16 | int32 | uint32 | single | double

Parameters

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Main

Specify the SPI module to which the SPI peripheral devices is connected.

Specify the pin name on the board to which the SPI peripheral devices is connected. The SPI controller pulls the SS pin of the selected peripheral to a low (0) value to start the communication. The peripheral is selected depending on the pin polarity that you specify in the Chip select pin polarity parameter. The controller can select only one peripheral at a time.

Select the order in which the data is transmitted.

  • Most significant bit (MSB) — Select MSB to send the most significant bit (MSB) first.

  • Least significant bit (LSB) — Select LSB to send the least significant bit (LSB) first.

An SPI controller sets the clock polarity (CPOL) and the clock phase (CPHA).

The combination of polarity and phase are referred to as SPI modes. The SPI modes 0–3 are shown in the table.

ModeClock Polarity (CPOL)Clock Phase (CPHA)
000
101
210
311

For more information on register read/write, see SPI Transfer Modes.

Specify this address as an integer or in hexadecimal format by using hex2dec(), for example, ‘hex2dec(‘20’)’.

Advanced

The logic levels supported by Chip select pin to select the SPI peripheral devices.

  • Active low — The device is enabled on logic low. The SPI peripheral devices gets enabled when its SS pin is set to low.

  • Active high — The device is enabled on logic high. The SPI peripheral devices gets enabled when its SS pin is set to high.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2018a