Limit to number of simultaneious PWM

ESP8266 (Adafruit Feather Huzzah) with individual LED’s driven by PWM on separate pins.

The code:

int pwmPins[] = {0, 1, 2, 3, 4, 5, 12, 13, 14, 15, 16};

void setup() {
    for (int i=0; i<11; i++) {
        pinMode(pwmPins[i], OUTPUT);  // not needed but doesn't seem to impact either.
        analogWrite(i, 900);
    }
}

void loop() {
}

Shows signals present on pins 0 through 5 but not 12 through 16.

Testing to see if it’s a quantity limit trying just 12 through 16 in the pwmPins array none work. Note there is no error messages.

Also try without the pinMode line (as some sources suggest it’s not needed)

Any ideas?

Esp8266 based boards do not have 16 useable gpio pins. From this page:

9 x GPIO pins - can also be used as I2C and SPI

What pins on the feather are you testing?

PaulRB:
What pins on the feather are you testing?

0, 1, 2, 3, 4, 5, 12, 13, 14, 15, 16.

FYI - correct there are not 16 GPIO pins. There are 9 on the Feather Huzzah and surprisingly, the TX (GPIO1) and RX (GPIO3) also present and act as GPIO’s with the PWM signal. https://cdn-learn.adafruit.com/assets/assets/000/046/249/original/adafruit_products_Huzzah_ESP8266_Pinout_v1.2-1.png?1504885873

smitthhyy:
surprisingly, the TX (GPIO1) and RX (GPIO3) also present and act as GPIO's

Not really a surprise, as long as your sketch does not contain Serial.begin(), they will be available as GPIO. However, if you connect an external signal to RX or use RX as an OUTPUT, that could conflict with the USB-serial chip and cause damage to the circuit.