Overview

The lpspi_polling_b2b_transfer example shows how to use LPSPI driver in polling way:

In this example , we need two boards, one board used as LPSPI master and another board used as LPSPI slave. The file ‘lpspi_polling_b2b_transfer_master.c’ includes the LPSPI master code.

  1. LPSPI master send/received data to/from LPSPI slave in polling . (LPSPI Slave using interrupt to receive/send the data)

Toolchain supported

  • IAR embedded Workbench 9.30.1

  • MCUXpresso 11.6.0

Hardware requirements

  • Mini/micro USB cable

  • MCX-N9xx-EVK board

  • Personal Computer

Board settings

To make the example work, connections needed to be as follows: Note: Jumper setting:

	MASTER           connect to           SLAVE
Pin Name   Board Location     Pin Name    Board Location
SOUT       J2 - 8           SIN         J2 - 10
SIN        J2 - 10          SOUT        J2 - 8
SCK        J2 - 12          SCK         J2 - 12
PCS0       J2 - 6           PCS0        J2 - 6
GND        J2 - 14          GND         J2 - 14

Other jumpers keep default configuration.

Prepare the Demo

  1. Connect a mini USB cable between the PC host and the MCU-Link USB port on the board.

  2. Open a serial terminal on PC for MCU-Link serial device with these settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  3. Download the program to the target board.

  4. Either press the reset button on your board or launch the debugger in your IDE to begin running the demo.

Running the demo

The following lines are printed to the serial terminal when the demo program is executed.

LPSPI board to board polling example.
This example use one board as master and another as slave.
Master uses polling way and slave uses interrupt way. 
Please make sure you make the correct line connection. Basically, the connection is: 
LPSPI_master --  LPSPI_slave   
   CLK       --    CLK  
   PCS       --    PCS 
   SOUT      --    SIN  
   SIN       --    SOUT 
   GND       --    GND 

 Master transmit:

  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F 10
 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F 20
 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F 30
 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40
 
LPSPI transfer all data matched! 

 Master received:

  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F 10
 11 12 13 14 15 16 17 18 19 1A 1B 1C 1D 1E 1F 20
 21 22 23 24 25 26 27 28 29 2A 2B 2C 2D 2E 2F 30
 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F 40

 Press any key to run again