ESP8266 Community Forum

- Mon Feb 15, 2016 2:58 pm #41191 Hi all, I've been following the ESP8266 for the last couple of weeks and after getting a simple working setup with AT firmware, I was really pleased to see the Arduino support and very happy when I was able to make an LED flash through GPIO2 :)

As part of learning more, I have a project in mind which needs me to sample audio, so I need to trigger an ISR very frequently. After reading and searching, I have the following code:

Code: Select alluint32_t curcount = 0;

void ICACHE_RAM_ATTR pwm_timer_isr(){
  if (curcount % 1000) {
    Serial.println ("1000 hit");
    Serial.printf("curcount is %d\n", curcount);
  }
  curcount++;
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("START1");
  timer1_disable();
  timer1_attachInterrupt(pwm_timer_isr);
  timer1_write(1);
  timer1_enable(TIM_DIV265, TIM_EDGE, TIM_LOOP);
  Serial.println("START2");
}

void loop() {
  // put your main code here, to run repeatedly:
  delay(1000);
}


Unfortunately, this only seems to reset every few seconds:

Code: Select all ets Jan  8 2013,rst cause:4, boot mode:(3,6)

wdt reset
load 0x4010f000, len 1264, room 16
tail 0
chksum 0x42
csum 0x42
~ld
START1
1000 hit
curcount is 1
1000 hit
curcount is 2
1000 hit
curcount is 3
1000 hit
curcount is 4
1000 hit
curcount is 5
1000
 ets Jan  8 2013,rst cause:4, boot mode:(3,6)

wdt reset
load 0x4010f000, len 1264, room 16
tail 0
chksum 0x42
csum 0x42
~ld
START1
1000 hit
curcount is 1
1000 hit
curcount is 2
1000 hit
curcount is 3
1000 hit
curcount is 4
1000 hit
curcount is 5
1000

Can anyone suggest what dumb mistake I'm making?

- Tue Oct 10, 2017 3:36 am #70762 There may be other problems with the code, but the most obvious thing is trying to write to the serial port from an interrupt routine, which would seem to be a very bad idea at the least.

Set a flag in the interrupt routine and do your serial port stuff in your loop() function.