SPI-Master-Slave

name	SPI-Master-Slave
boards	da14531
keywords	SPI Master-slave
description	This example describes how to perform SPI data buffer transmission/reception between two DA14531 devices via DMA. The project is split in two parts: the Master Board and the Slave Board.

DA14531 SPI Master Slave example

Example description

This example describes how to perform SPI data buffer transmission/reception between two DA14531 devices via DMA. The project is split in two parts: The master board and the slave board.

HW and SW configuration

Hardware configuration

• This example runs on the DA1453x Bluetooth Smart SoC devices.
• Two DA14531 or DA1453x Pro Development Kits are needed for this example. One will act as master, the other as slave.
• You need to make the following interconnections between the two DA14531 or DA1453x Pro Development Kits. The interconnections between the two DA145xx Pro Development Kits are given in the user_periph_setup.h file, on your setup, the SPI signals (CLK, MOSI, MISO, SC) need to have a 1kOhm resistor each in series and the SPI CLK must be in a twisted-pair configuration with the GND.
• Also, on each board you must connect P05 (P25 on the J2 DA14531 Signals) to UTX pin 17 on J1 (J5.12) in order to have UART console logging.

Software configuration

• This example requires:
  • SDK v6.0.16 or later
  • SEGGER’s J-Link tools should be downloaded and installed.

How to run the example

For the initial setup of the project that involves linking the SDK to this SW example, please follow the readme here.

Compile and run

• Run master SPI Keil project. Run the python script to import needed files from the SDK (You can refer to the previous section)

• Under this folder: SPI_Master\project_environment open and start Keil µVision.

• Run slave SPI Keil project. Run the python script to import needed files from the SDK (You can refer to the previous section)

• Under this Folder: SPI_Slave\project_environment open and start Keil µVision.

• You build/download/run first the DA14531_SLAVE to one of the boards and then you build/download/run the DA14531_MASTER.

• You open two UART terminals for logging messages from both the master and the slave.

SPI Master/Slave communication

At the beginning of the main program the system_init() is called for system initialization. The SPI communication is initialized during the peripheral initialization through the function periph_init() function. The spi_transfer function is called to start sending/receiving data to/from SPI in full duplex mode. The spi_master_demo_out_buffer and spi_slave_demo_out_buffer are a predefined buffers (12 bytes) with data to send/receive to/from SPI. The SPI master starts the communication by sending spi_master_demo_out_buffer and receiving spi_slave_demo_out_buffer. The callback function spi_transfer_user_callback is used to check the transfer status and to return in interrupt/DMA-driven transferring operations. Finally,

Expected Results: UART Output

For each Board you need to Open a serial port with the following parameters.

	- baudrate: 115200
	- data: 8 bits
	- stop: 1 bit
	- parity: None
	- flow  control: none

• As soon as the examples run on both boards (Slave and master) the following messages should appear on the terminals.

The following will be printed on the master and slave sides:

Expected Results: Signal Outputs

Further reading

• Wireless Connectivity Forum

Known Limitations

• There are no known limitations for this example. But you can check and refer to the following application note for SDK6 known limitations

Feedback and support ?

If you have any comments or suggestions about this document, you can contact us through:

• Wireless Connectivity Forum

• Contact Technical Support

• Contact a Sales Representative