0.2 V on ESP32 WROOM pin 14 + GND, idea?

[Modesty]

Hi

My ESP32 WROOM gives only 0.2v between ground and pin 14, what should I expect?

I will turn on a SSD relay, but of course nothing happens...

Previously I tested Wemos ESP8266, that pin gave 3.3V

Any idea?

code:

const int ssrPin = 14; 
void setup() {
  pinMode(ssrPin, OUTPUT);
  Serial.begin(115200); 
  Serial.println("Arduino SSR Control");   
}

void loop() {
  digitalWrite(ssrPin, HIGH); 
  Serial.println("SSR turned ON"); 
  delay(3000); 
  digitalWrite(ssrPin, LOW); // Set ssrPin low
  Serial.println("SSR turned OFF");
  delay(3000); 

[Idahowalker]

3.3V is expected on the GPIO pins of a ESP32 development module. Is that V's measured without a load on the pin?

[apf1979]

Are you sure you're measuring Arduino pin 14? The schematic and Arduino pins vary.

[LarryD]

G14 is pin 13 on the ESP-WROOM-32

[Modesty]

Hi

I can have mixed pins but...

Anything I don't understand?

I use pin 14 on board + GND, according to pinout it is GPIO14:

Espressif:

[Modesty]

0.2 fixed mcu broken. New mcu all ok

[GolamMostafa]

@LarryD

G14 is pin 13 on the ESP-WROOM-32

Shown below (Fig-2) is a pin mapping diagram among 48-pin LX6 Microcontroller, 38-pin ESP-WROOM-32 Module, and 30-pin ESP32S Dev Kit, which has been prepared based on Espressif's official documents. Here, in this diagram, there is no G14.

Figure-1

Figure-2:

@Modesty

My ESP32 WROOM

Are you referring to: ESP-WROOM-32 Module based 30-pin ESP32S Dev Kit of Fig-1 (upper)? There are many versions of ESP32 Dev Kit.

[Modesty]

@GolamMostafa

there is no G14.

I cant aswer other than my wroom have gpio14, and its working for me, ref picture i added 2 days ago.

[GolamMostafa]

My ESP32S shows:
V_OL = 0.0V (max: 0.33V)
V_OH = 3.0V (min: 2.64V)

The above readings agree with the data sheets (Fig-1:.

Figure-1:

Test Sketch:

void setup() 
{
  pinMode(14, OUTPUT);
  digitalWrite(14, LOW);
  delay(10000);  
  digitalWrite(14, HIGH);
}

void loop() {}

[Modesty]

Thanks for all help. My system is now working

From datasheet: esp32-wroom-32_datasheet_en.pdf

Here is the WEB GUI for my fish feeder:

[GolamMostafa]

IO14/Pin-13 of RF Shielded ESP-ROOM-32 Module is not exposed to user via header pin. It is connected at D14/Pin-11 of the 30-Pin ESP32S Dev Kit (Fig-1, 2) of post #7.