C28x SPI Receive

Receive data through Serial Peripheral Interface (SPI) on target

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
C2000 Microcontroller Blockset / F28p55x
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32F4xx Based Boards
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32F7xx Based Boards
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32G4xx Based Boards
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32H7xx Based Boards
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32L4xx Based Boards
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32L5xx Based Boards
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32U5xx Based Boards
Embedded Coder Support Package for STMicroelectronics STM32 Processors / STM32WBxx Based Boards

Description

The SPI Receive block supports synchronous, serial peripheral input/output port communications between the processor and external peripherals or other controllers. The block can run in either peripheral or controller mode. In controller mode, the SPISIMO pin transmits data, and the SPISOMI pin receives the data. When controller mode is selected, the SPI initiates the data transfer by sending a serial clock signal (SPICLK), which is used for the entire serial communications link. Data transfers are synchronized to this SPICLK, which enables both controller and peripheral to send and receive data simultaneously. The maximum frequency for the clock is one quarter of the processor clock frequency.

The SPI device receives data and places the data in the receive buffer. The SPI Receive block reads the data from the receive buffer. In controller mode, the C28x SPI Transmit block initiates SPI transmission by writing data to the transmit buffer. Then, the data received in the receive buffer is read by the SPI Receive block. In peripheral mode, the SPI Receive block is used to read the data in the receive buffer, which is received from the controller. Then, the data is written into the transmit buffer using the SPI Transmit block. From the transmit buffer, the data is sent to the controller.

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

Examples

Using SPI to Read and Write Data to SPI EEPROM

Configure and use SPI blocks to read and write data.

Open Model

Ports

Output

expand all

Rx — SPI receive data
vector

The data read from the device over the SPI interface.

Data Types: uint16

Status — SPI receive status
`0` | `1` | `2`

Status of receipt of data. Error status values indicate:

0 — No errors.
1 — Data loss occurred because of overflow.
2 — Data not ready. A time out occurred while the block was waiting to receive data.

Dependencies

This port appears only when Enable blocking mode is not selected.

Data Types: uint16

Parameters

expand all

Main

SPI module — SPI module to read data
`SPI_A` (default) | `SPI_B` | `SPI_C` | `SPI_D`

The SPI 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 used for SPI communication mode. This parameter must be the same for both transmit and receive blocks.

Clock phase — SPI clock phase
`No_delay` (default) | `Delay_half_cycle`

The clock phase used for SPI communication mode. This parameter must be the same for both transmit and receive blocks.

Output data length — SPI output data length
`1` (default) | positive integer

The received data is a vector of type uint16 and the data length is as specified in this parameter (not bytes).

Enable blocking mode — Enable SPI blocking mode
`off` (default) | `on`

When this option is selected, the algorithm waits until data is received before continuing processing.

Sample time — SPI sample time selection
`0.1` (default) | `–1` | scalar

Sample time for the block in seconds. To execute this block asynchronously, set this parameter to -1.

Advanced

Data bits — Number of bits in SPI transfer
`8` (default) | integer in [1 16]

Length in bits of each transmitted or received character. For example, if you select 8, the maximum value that can be transmitted using SPI is 2⁸–1. If you send data greater than this value, the buffer overflows. This parameter must be the same for both transmit and receive blocks.

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 provided 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 instead of the STE pin of the SPI peripheral to select/deselect SPI peripheral devices. The SPI Receive block deselects the peripheral using GPIO pins after receiving data. To select the peripheral, the C28x SPI Transmit block must be used along with the SPI Receive block. Use this option only in controller mode. Select the Enable blocking mode option to ensure that the SPI transmission is complete before the peripheral is deselected.

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

Chip select pin — SPI peripheral select pin
`0` (default) | positive integer scalar

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

Dependencies

This option 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

C28x SPI Receive

Description

Examples

Using SPI to Read and Write Data to SPI EEPROM

Ports

Output

Rx — SPI receive data vector

Status — SPI receive status 0 | 1 | 2

Dependencies

Parameters

Main

SPI module — SPI module to read data SPI_A (default) | SPI_B | SPI_C | SPI_D

Clock polarity — SPI clock polarity Rising_edge (default) | Falling_edge

Clock phase — SPI clock phase No_delay (default) | Delay_half_cycle

Output data length — SPI output data length 1 (default) | positive integer

Enable blocking mode — Enable SPI blocking mode off (default) | on

Sample time — SPI sample time selection 0.1 (default) | –1 | scalar

Advanced

Data bits — Number of bits in SPI transfer 8 (default) | integer in [1 16]

Chip select calling method — Method to select SPI peripheral device Provided by the SPI peripheral (default) | Explicit GPIO calls

Chip select pin polarity — SPI peripheral select pin polarity Active low (default) | Active high

Dependencies

Chip select pin — SPI peripheral select pin 0 (default) | positive integer scalar

Dependencies

Extended Capabilities

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

Version History

See Also

Rx — SPI receive data
vector

Status — SPI receive status
`0` | `1` | `2`

SPI module — SPI module to read data
`SPI_A` (default) | `SPI_B` | `SPI_C` | `SPI_D`

Clock polarity — SPI clock polarity
`Rising_edge` (default) | `Falling_edge`

Clock phase — SPI clock phase
`No_delay` (default) | `Delay_half_cycle`

Output data length — SPI output data length
`1` (default) | positive integer

Enable blocking mode — Enable SPI blocking mode
`off` (default) | `on`

Sample time — SPI sample time selection
`0.1` (default) | `–1` | scalar

Data bits — Number of bits in SPI transfer
`8` (default) | integer in [1 16]

Chip select calling method — Method to select SPI peripheral device
`Provided by the SPI peripheral` (default) | `Explicit GPIO calls`

Chip select pin polarity — SPI peripheral select pin polarity
`Active low` (default) | `Active high`

Chip select pin — SPI peripheral select pin
`0` (default) | positive integer scalar

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