IO34,35,36,39

Schematics, Example Code and Q&A
Airhead
Posts: 5
Joined: Sun Feb 24, 2019 4:43 pm

IO34,35,36,39

Unread post by Airhead »

I can't seem to digitalWrite IO34,35,36,39
Is there something special about them?
I wrote a 'blinker' and they won't budge.

Code: Select all

#define csP1  34
#define csP2  35
#define csP3  36
#define csP4  39

#define miso  12
#define mon  16

void setup() 
{
  pinMode(csP1, OUTPUT);
  pinMode(csP2, OUTPUT);
  pinMode(csP3, OUTPUT);
  pinMode(csP4, OUTPUT);
  pinMode(miso, OUTPUT);
  pinMode(mon, OUTPUT);
}

void loop() 
{
  digitalWrite(csP1, HIGH);
  digitalWrite(csP2, HIGH);  
  digitalWrite(csP3, HIGH);
  digitalWrite(csP4, HIGH);  
  digitalWrite(miso, HIGH);
  digitalWrite(mon, HIGH);
  delay(15);
  digitalWrite(csP1, LOW);
  digitalWrite(csP2, LOW);  
  digitalWrite(csP3, LOW);
  digitalWrite(csP4, LOW);  
  digitalWrite(miso, LOW);
  digitalWrite(mon, LOW);
  delay(15);  

}
Airhead
Posts: 5
Joined: Sun Feb 24, 2019 4:43 pm

Re: IO34,35,36,39

Unread post by Airhead »

Yay! I get to answer my own question Again.
In the Espressif manual,
Appendix A - ESP32 Pin Lists
A.1.2 -- GPIO pins 34-39 are input-only.

GPIO pins 34-39 are input-only. These pins do not feature an output driver or internal pull-up/pull-down circuitry.
The pin names are: SENSOR_VP (GPIO36), SENSOR_CAPP (GPIO37),
SENSOR_CAPN (GPIO38), SENSOR_VN (GPIO39), VDET_1 (GPIO34), VDET_2 (GPIO35).
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