IDC
backlight PWM test app. PWM on pin 21 trigger output on pin 22.
Fork of
PwmOut_HelloWorld
by 
Mbed
Revision 2:cfacbc7be12b, committed 2017-06-22
- Comitter:
- ChrisABailey
- Date:
- Thu Jun 22 19:10:11 2017 +0000
- Parent:
- 1:5160ea45399b
- Commit message:
- version for testing FES 5.7 backlight driver
Changed in this revision
diff -r 5160ea45399b -r cfacbc7be12b FastPWM.lib --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/FastPWM.lib Thu Jun 22 19:10:11 2017 +0000 @@ -0,0 +1,1 @@ +http://developer.mbed.org/users/Sissors/code/FastPWM/#e880dcb178f4
diff -r 5160ea45399b -r cfacbc7be12b main.cpp
--- a/main.cpp Sun Sep 21 06:39:30 2014 +0000
+++ b/main.cpp Thu Jun 22 19:10:11 2017 +0000
@@ -1,12 +1,129 @@
#include "mbed.h"
+#include <ctype.h>
+#include "FastPWM.h"
-PwmOut led(LED1);
+DigitalOut led1(LED1);
+DigitalOut led2(LED2);
+DigitalOut led3(LED3);
+DigitalOut led4(LED4);
+FastPWM pwm(p21);
+DigitalOut trigger(p22);
+//AnalogIn analog_value(p20);
+Serial pc(USBTX, USBRX);
+double dutyCycle=.01;
+
+void seekPWM(double newDuty)
+{
+ if (dutyCycle<0.01 or newDuty <0.01)
+ {
+ if (newDuty > dutyCycle) {
+ while (newDuty/dutyCycle > 2) {
+ dutyCycle = dutyCycle * 1.5;
+ trigger=0;
+ pwm.write(dutyCycle);
+ trigger=1;
+ wait_ms(100);
+ }
+ } else {
+ while (newDuty/dutyCycle < .5) {
+ dutyCycle = dutyCycle * 0.75;
+ trigger=0;
+ pwm.write(dutyCycle);
+ trigger=1;
+ wait_ms(100);
+ }
+ }
+ }
+ trigger=0;
+ dutyCycle = newDuty;
+ pwm.write(dutyCycle);
+ trigger=1;
+
+
+}
+
int main() {
+ char current_char=0;
+
// specify period first
- led.period(4.0f); // 4 second period
- led.write(0.50f); // 50% duty cycle, relative to period
+ //led.period(0.0050f); // 200 Hz
+ //pwm.period(0.0100f); // 100 Hz
+
+ pwm.period_ms(10);
+ //led.write(0.10f); // 10% duty cycle, relative to period
+ pwm.write(dutyCycle); // 1%
//led = 0.5f; // shorthand for led.write()
//led.pulsewidth(2); // alternative to led.write, set duty cycle time in seconds
- while(1);
+
+
+ while(1)
+ {
+
+ pc.printf("Current duty cycle = %f \r\n ", dutyCycle);
+ pc.printf("U to increase duty cycle \r\n ");
+ pc.printf("D to decrease duty cycle \r\n ");
+ pc.printf("R to ramp duty cycle \r\n ");
+ pc.printf("Command?");
+ current_char = pc.getc();
+ pc.printf("%c\n\r",current_char);
+
+ switch (tolower(current_char))
+ {
+
+ case 'u':
+ {
+ dutyCycle = dutyCycle + 0.0002;
+ trigger=1;
+ }
+ break;
+ case 'd':
+ {
+ dutyCycle = dutyCycle - 0.0002;
+ trigger=1;
+ }
+ break;
+ case 'r':
+ {
+ trigger = 0;
+ seekPWM(0.0001);
+ wait(1.0);
+ trigger=0;
+ seekPWM(0.05);
+ trigger=0;
+ /*
+ trigger=0;
+ dutyCycle = 0.001;
+ pwm.write(dutyCycle);
+ wait(1.0);
+ //int pulseWidthUs = 10;
+ for (int i=0; i< 10;i++)
+ {
+ trigger=1;
+ pwm.write(dutyCycle);
+ //pwm.pulsewidth_us(pulseWidthUs);
+ pulseWidthUs *= 2;
+ wait_ms(10);
+ trigger=0;
+ wait(1.0);
+
+ //dutyCycle = dutyCycle+(.0001);
+ pulseWidthUs = pulseWidthUs + 10;
+ led1.write(i&0x01);
+ led2.write((i&0x02)>>1);
+ led3.write((i&0x04)>>2);
+ led4.write((i&0x08)>>3);
+ }
+ */
+
+ }
+ break;
+ }
+ dutyCycle = dutyCycle < 1.0 ? dutyCycle : 1.0;
+ dutyCycle = dutyCycle > 0.0001 ? dutyCycle : 0.0001;
+ pwm.write(dutyCycle);
+ wait_ms(10);
+ trigger=0;
+
+ }
}
\ No newline at end of file
diff -r 5160ea45399b -r cfacbc7be12b mbed.bld --- a/mbed.bld Sun Sep 21 06:39:30 2014 +0000 +++ b/mbed.bld Thu Jun 22 19:10:11 2017 +0000 @@ -1,1 +1,1 @@ -http://mbed.org/users/mbed_official/code/mbed/builds/552587b429a1 \ No newline at end of file +http://mbed.org/users/mbed_official/code/mbed/builds/da0ca467f8b5 \ No newline at end of file