Stefan Waldschmidt / Mbed OS Test_GPIO-out_Toggle_Time

Test maximal GPIO output performance by toggling a GPIO output pin as fast as possible.

This mbed program creates a thread with Realtime Priority to do nothing but to toggle a GPIO output as fast as possible.

Measurements are performed on a NUCLEO-F767ZI board https://os.mbed.com/platforms/ST-Nucleo-F767ZI/.

  • STM32F767ZIT6 @ 216 MHz
  • Duration of high or low phases: 4 nsec - 10 nsec (resulting is something from 50 MHz to 125 MHz)

main.cpp@0:f122acadb07b, 2019-05-13 (annotated)

Committer:
stefanwaldschmidt
Date:
Mon May 13 12:28:40 2019 +0000
Revision:
0:f122acadb07b
initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
stefanwaldschmidt 0:f122acadb07b 1 /*
stefanwaldschmidt 0:f122acadb07b 2 Test GPIO-output toggle time
stefanwaldschmidt 0:f122acadb07b 3
stefanwaldschmidt 0:f122acadb07b 4 Hardware: NUCLEO-F767ZI
stefanwaldschmidt 0:f122acadb07b 5 STM32F767ZIT6 @ 216 MHz
stefanwaldschmidt 0:f122acadb07b 6 Libraries:
stefanwaldschmidt 0:f122acadb07b 7 mbed-os-5.12.3
stefanwaldschmidt 0:f122acadb07b 8 Measured gpio_out frequency
stefanwaldschmidt 0:f122acadb07b 9 * total period: 8 nsec - 20 nsec (125 MHz - 50 MHz)
stefanwaldschmidt 0:f122acadb07b 10 */
stefanwaldschmidt 0:f122acadb07b 11
stefanwaldschmidt 0:f122acadb07b 12 #include "mbed.h"
stefanwaldschmidt 0:f122acadb07b 13
stefanwaldschmidt 0:f122acadb07b 14 DigitalOut gpio_out(PC_8);
stefanwaldschmidt 0:f122acadb07b 15
stefanwaldschmidt 0:f122acadb07b 16 void run()
stefanwaldschmidt 0:f122acadb07b 17 {
stefanwaldschmidt 0:f122acadb07b 18 while (true) {
stefanwaldschmidt 0:f122acadb07b 19 gpio_out = 1;
stefanwaldschmidt 0:f122acadb07b 20 gpio_out = 0;
stefanwaldschmidt 0:f122acadb07b 21 gpio_out = 1;
stefanwaldschmidt 0:f122acadb07b 22 gpio_out = 0;
stefanwaldschmidt 0:f122acadb07b 23 }
stefanwaldschmidt 0:f122acadb07b 24 }
stefanwaldschmidt 0:f122acadb07b 25
stefanwaldschmidt 0:f122acadb07b 26 int main()
stefanwaldschmidt 0:f122acadb07b 27 {
stefanwaldschmidt 0:f122acadb07b 28 Thread *thread = new Thread(osPriorityRealtime);
stefanwaldschmidt 0:f122acadb07b 29
stefanwaldschmidt 0:f122acadb07b 30 thread->start(run);
stefanwaldschmidt 0:f122acadb07b 31
stefanwaldschmidt 0:f122acadb07b 32 while (true) {
stefanwaldschmidt 0:f122acadb07b 33 wait(0.1); // 100 ns
stefanwaldschmidt 0:f122acadb07b 34 }
stefanwaldschmidt 0:f122acadb07b 35 }