Serial2 initialization on ESP32-WROOM-32E causes reinitialization of digital pin 4

[CalamaroGigante]

Board

Firebeetle v1

Device Description

Development board

Hardware Configuration

Serial2 initializing

Version

v3.0.0

IDE Name

Arduino IDE 2.3.2

Operating System

Windows 10

Flash frequency

?

PSRAM enabled

yes

Upload speed

115200

Description

Initializing Serial2 causes IO4 to be set to HIGH, and it is impossible to control via digitalWrite, unless reinitialized
A rollback to previous revision solves the issues

Sketch

#include <Arduino.h>


#define PIN_ENABLE_HOHC 4


void setup() 
{
  pinMode(PIN_ENABLE_HOHC, OUTPUT);// Set as output mode 
  digitalWrite(PIN_ENABLE_HOHC, LOW);   
  Serial.begin(115200);
  Serial.println("First");
  delay(5000);
  Serial2.begin(9600);  //this instruction causes digital pin 4 to go HIGH
  Serial.println("Second");
  delay(5000);
}

void loop() 
{
  pinMode(PIN_ENABLE_HOHC, OUTPUT);//Still high
  digitalWrite(PIN_ENABLE_HOHC, LOW);   
}

Debug Message

Compiles OK, no errors.

Other Steps to Reproduce

No response

I have checked existing issues, online documentation and the Troubleshooting Guide

• I confirm I have checked existing issues, online documentation and Troubleshooting guide.

[CalamaroGigante]

#include <Arduino.h>

#define PIN_ENABLE_HOHC 4

void setup()
{
pinMode(PIN_ENABLE_HOHC, OUTPUT);// Set as output mode
digitalWrite(PIN_ENABLE_HOHC, LOW);
Serial.begin(115200);
Serial.println("First");
delay(5000);
Serial2.begin(9600); //this instruction causes digital pin 4 to go HIGH
Serial.println("Second");
delay(5000);
}

void loop()
{
//pinMode(PIN_ENABLE_HOHC, OUTPUT); if this instruction is commented
digitalWrite(PIN_ENABLE_HOHC, LOW); //this one does not work
}

[SuGlider]

@CalamaroGigante - Arduino Core 3.0.0 and 2.0.15+ has changed ESP32 Serial2 pins to RX = GPIO4 and TX = GPIO25.
This is the reason for this issue. Please check PR# #8800

In order to use GPIO4 and Serial2, please initialize it using the call:
Serial2.begin(baud_rate, uart_mode, RX2_pin, TX2_pin);

Based on your example code: Serial2.begin(9600, SERIAL_8N1, RX2_pin, TX2_pin);

New Pins:

	Name	ESP32	S2	S3	C3	C6	H2
UART0 RX	SOC_RX0	3	44	44	20	17	23
UART0 TX	SOC_TX0	1	43	43	21	16	24
UART1 RX	RX1	26	4	15	18	4	0
UART1 TX	TX1	27	5	16	19	5	1
UART2 RX	RX2	4	--	19	--	--	--
UART2 TX	TX2	25	--	20	--	--	--

[VojtechBartoska]

I am closing this as answered.