3.0.0 Alpha2 :: Serial + RMT doesn't work.

[SuGlider]

Board

ESP32

Device Description

DevKit

Hardware Configuration

None

Version

latest master (checkout manually)

IDE Name

Arduino IDE

Operating System

Win11

Flash frequency

80Mhz

PSRAM enabled

no

Upload speed

115200

Description

Starting UART0 and then using RX/TX Pins for RMT and starting again UART0 fails.
It works with 2.0.14, but it doesn't with 3.0.0-Alpha2.

The execution sequence can be seen in the example bellow.

Sketch

void setup() {
  Serial.begin(115200);
  delay(1000);
  Serial.println("TESTING ... 1");
  Serial.flush();

  const uint8_t testedPin = 1; // ESP32 UART0 RX=3 | TX = 1
#if 0
  // Arduino Core 2.0.4 -- working fine.
  rmt_obj_t* rmt_send = NULL;
  if ((rmt_send = rmtInit(testedPin, RMT_TX_MODE, RMT_MEM_64)) == NULL) {
    Serial.println("init sender failed\n"); // RX(3) / TX(1) is being used now... it may not print anything.
  }
  float realTick = rmtSetTick(rmt_send, 100);
  Serial.printf("real tick set to: %fns\n", realTick); // not to be seen... as we use TX0 in RMT.
#else
  // Arduino Core 3.0.0-Alpha2 -- working fine.
  if (!rmtInit(testedPin, RMT_TX_MODE, RMT_MEM_NUM_BLOCKS_1, 10000000)) {
    Serial.println("init sender failed\n");
  }
  Serial.println("real tick set to: 100ns");
#endif
  delay(500);
  Serial.end();
  Serial.begin(115200);
  Serial.setPins(3, 1);
  Serial.println("TESTING ... 2");
  Serial.flush();
}

void loop() {
  Serial.println("Looping ...");
  delay(5000);
}

Debug Message

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff0030,len:1416
load:0x40078000,len:14804
load:0x40080400,len:4
load:0x40080404,len:3356
entry 0x4008059c
TESTING ... 1
********************===> UART0 stops working and it doesn't recover

Other Steps to Reproduce

None.

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

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

[SuGlider]

Expected Ouput (obtained with 2.0.14):

ets Jul 29 2019 12:21:46

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee
clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
mode:DIO, clock div:1
load:0x3fff0030,len:1344
load:0x40078000,len:13964
load:0x40080400,len:3600
entry 0x400805f0
TESTING ... 1
TESTING ... 2
Looping ...
Looping ...
Looping ...

[lucasssvaz]

Update:
Same thing happens with SPI in some cases. Still not sure why.

[SuGlider]

Update: Same thing happens with SPI in some cases. Still not sure why.

This shall be fully fixed by #8820
@lucasssvaz - please let me know about your CI testing.