C28x SPI Controller Transfer

Write data to and read data from SPI peripheral device

• 

Libraries:
C2000 Microcontroller Blockset / C2802x
C2000 Microcontroller Blockset / C2803x
C2000 Microcontroller Blockset / C2805x
C2000 Microcontroller Blockset / C2806x
C2000 Microcontroller Blockset / C280x
C2000 Microcontroller Blockset / C281x
C2000 Microcontroller Blockset / C2833x
C2000 Microcontroller Blockset / C2834x
C2000 Microcontroller Blockset / F280013x
C2000 Microcontroller Blockset / F280015x
C2000 Microcontroller Blockset / F28002x
C2000 Microcontroller Blockset / F28003x
C2000 Microcontroller Blockset / F28004x
C2000 Microcontroller Blockset / F2807x
C2000 Microcontroller Blockset / F2837xD
C2000 Microcontroller Blockset / F2837xS
C2000 Microcontroller Blockset / F2838x / C28x
C2000 Microcontroller Blockset / F28M35x / C28x
C2000 Microcontroller Blockset / F28M36x / C28x
C2000 Microcontroller Blockset / F28p65x

Description

The C28x SPI Controller Transfer block writes data to and reads data from a peripheral device over the Serial Peripheral Interface (SPI). The block runs in controller mode. The block outputs an array of the same size and data type as the input values. You can use this block with the Byte Pack and Byte Unpack blocks for heterogeneous data type transfers.

Configure the SPI modules for the specific hardware board by navigating to Hardware Implementation > Target hardware resources. Verify that these settings meet the requirements of your application.

Using this block, you can access an SPI device to measure quantities such as temperature and pressure.

Examples

Using SPI to Read and Write Data to SPI EEPROM

Configure and use SPI blocks to read and write data.

Open Model

Ports

Input

Tx — Data written to registers of SPI peripheral device (MOSI)

vector

The data written by the block to the registers of a peripheral device over the SPI interface.

Data Types: uint16

Output

Rx — Data read from registers of SPI peripheral device (MISO)

vector

The data read by the block from the registers of a peripheral device over the SPI interface.

Data Types: uint16

Parameters

Main

SPI module — SPI module to write and read data

SPI_A (default) | SPI_B | SPI_C | SPI_D

The SPI peripheral module to which the SPI peripheral device is connected. Each processor has a different number of modules.

Clock polarity — SPI clock polarity

Rising_edge (default) | Falling_edge

The clock polarity (CPOL) for SPI communication mode.

Clock phase — SPI clock phase

No_delay (default) | Delay_half_cycle

The clock phase (CPHA) for SPI communication mode.

Enable register address — Enables SPI register address

on (default) | off

Enables the Register address parameter.

Register address — SPI register address

0 (default) | positive integer scalar | positive integer vector

The peripheral register address from which the block reads data.

For example, if we consider the Using SPI to Read and Write Data to SPI EEPROM example, to write the EEPROM memory by address 32 (0x0020) and the write command 2, the entry can be [2 0 32] which corresponds to write command followed by 16-bit address and the data at the input port.

Here the address is split as 0x00 (0) and 0x20 (32) as two 8-bit numbers and is entered in the register address. The reason for splitting it as two 8-bit numbers is the setting in Data bits parameter in Advanced tab. Since this is set to 8 bits, the data in the vector format should not be considered more than 8-bit. If you select the parameter as 16, then 0 and 32 corresponds to 32-bit address (0x00000020) instead of 16-bit.

Dependencies

This parameter appears only when you select Enable register address.

Advanced

Data bits — Number of bits in SPI transfer

8 (default) | integer in the range [1 16]

Length in bits of each transmitted or received character, specified as an integer in [1 16]. For example, if you select 8, the maximum value that can be transmitted using SPI is 2⁸ – 1. If you send data values greater than this value, the buffer overflows.

Chip select calling method — Method to select SPI peripheral device

Provided by the SPI peripheral (default) | Explicit GPIO calls

The SPI controller uses these methods to select SPI peripheral devices.

• Provided by the SPI peripheral — The SPI controller uses the STE pin assignment parameter in Hardware Implementation > Target Hardware Resources > SPI to select the peripheral device. peripheral select and deselect are handled by the SPI peripheral.

• Explicit GPIO calls — The SPI controller uses the general purpose input/output pins explicitly to select/deselect SPI peripheral devices. The SPI controller Transfer block selects the peripheral before data is transmitted and deselects the peripheral after data is received using GPIO pins.

Chip select pin polarity — SPI peripheral select pin polarity

Active low (default) | Active high

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

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

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

Dependencies

This parameter appears only when Chip select calling method is set to Explicit GPIO calls.

Chip select pin — SPI peripheral select pin

1 (default) | positive integer scalar

The general purpose input/output pin that serves as peripheral select for SPI.

Dependencies

This parameter appears only when Chip select calling method is set to Explicit GPIO calls.

Extended Capabilities

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

Version History

Introduced in R2017b