Hardware requirements

  • Type-C USB cable

  • FRDM-MCXL255 board

  • Personal Computer

Board settings

LPSPI:

       MASTER(SPI1)      connect to        SLAVE(SPI1)
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               PCS1        J2-6
GND        J2-14              GND         J2-14

Make sure you have solder bridges SJ1 and SJ2 set to

  • 2-1 for the main core (cm33)

Prepare the Demo

  1. Connect a USB Type-C cable between the host PC and the MCU-Link USB port on the target 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