analogWrite to LED_PWR and digitalWrite after analogWrite

[FemmeVerbeek]

It looks like two bugs to me.

• analogWrite to LED_PWR hangs up the program
• digitalWrite to any pin stops working after being preceded by a call to analogWrite to the same pin.

my not so beautiful workaround

void digitalWrite2(int pinnr , boolean pinhigh){ if (pinnr==LED_PWR) digitalWrite(LED_PWR, pinhigh); else analogWrite(pinnr, 255*pinhigh); } void analogWrite2(int pinnr ,uint8_t value){ if (pinnr==LED_PWR) digitalWrite(pinnr,value>127); else analogWrite(pinnr,value); }

It would be better to solve it by redefining the functions itself but so that it still compiles for other boards.

• Is there an #ifdef compiler directive to check that we are compiling for this type of board.
• while redefining, how would you point back to the orginal funtions

[facchinm]

Hi @FemmeVerbeek analogWrite(LED_PWR, 10); should just work in any condition unless you already have more than 4 other PWM active (I just tested it). The reason is this assert (https://github.com/ARMmbed/mbed-os/blob/master/targets/TARGET_NORDIC/TARGET_NRF5x/TARGET_NRF52/pwmout_api.c#L146) that checks how many PWM channels are already in use. Is this your case?

[FemmeVerbeek]

Hi Martino,
Thx for looking into it. I was making art with the onboard leds.
  :-)

It looks like analog calling the 5th channel is what caused the
  hanging problem.  

Apparently assigning a PWM channel stops digitalWrite from
  working on that pin . 

Is there a (user friendly) way to free up the Pin channel in a
sketch, so that digitalWrite works again? Possibly reassign the
channel to another pin?
Kind regards
Femme Verbeek.

code
void setup() 
  { pinMode(LED_BUILTIN,OUTPUT);
    analogWrite(LED_BUILTIN,75);
    digitalWrite(LED_BUILTIN,1);
    delay(1000);
    digitalWrite(LED_BUILTIN,0);
  }
  void loop(){}

[JeffAnton]

I've hit this problem also. digitalWrite after an analogWrite to the same pin does not work. Once I saw this report I changed my digitalWrite calls into analogWrite with values of 0 or 255 and my project is working properly. BTW: I have four analogWrite pins in use.