USB is randomly disconnected from ESP32-S3

[sblantipodi]

Board

Lolin ESP32-S3

Device Description

Plain Lolin ESP32-S3 board

Hardware Configuration

No GPIO used

Version

v3.0.1

IDE Name

PlatformIO

Operating System

Windows 11

Flash frequency

240MHz

PSRAM enabled

no

Upload speed

115200

Description

the sketch below hangs from time to time.
the USB from S3 is disconnected and you need to power down/on the ESP device to get USB working again.

Sketch

byte pre[CONFIG_PREFIX_LENGTH];

Serial.begin(115200);
Serial.setRxBufferSize(1500);
size_t prefixLength = Serial.readBytes((byte *) pre, 1500);

Debug Message

-

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.

[me-no-dev]

requires minimal sketch that we can compile to reproduce.

[SuGlider]

What is the USB CDC settings, Hardware Serial JTAG or OTG TinyUSB?

How is it detecting that USB has disconnected?

Could it be a USB Cable/plug problem instead?

When Log Output Level is debug, do you see any messages in the UART0?

[sblantipodi]

requires minimal sketch that we can compile to reproduce.

it's difficult to give you a minimal sketch since there is a PC part also needed that sends the data to the ESP.

What is the USB CDC settings, Hardware Serial JTAG or OTG TinyUSB?

problem happen with both Hardware CDC and TinyUSB.

How is it detecting that USB has disconnected?

I can hear the Windows sound when a USB device is disconnected. And after the sound no device is present in the windows device manager.

Could it be a USB Cable/plug problem instead?

I tried a lot of cable and USB ports, I doubt. I have a firmware that is used by a lot of users, and all users are reporting the same problem with difference PCs and obviously cables.

When Log Output Level is debug, do you see any messages in the UART0?

no

[SuGlider]

@sblantipodi -
I have tested it with Arduino 3.0.3, using an ESP32-S3 + HW Serial JTAG USB port. It worked fine for about 3 hours receiving data from a Python script.

Sketch:

// using S3 devKit - RGB LED will indicate that CDC has been
// open by Python Script.
// If S3 resets, Python script will hang/fail and LED will be kept RED

// Serial is the USB port - Enable CDC on Boot!
// Serial0 is the UART0 - Console -- Serial Monitor

void setup() {
  neopixelWrite(RGB_BUILTIN, RGB_BRIGHTNESS, 0, 0);  // Red
  Serial.begin();
  Serial.setRxBufferSize(1500);
  Serial.setTimeout(10); // reduces the time waiting for receiving bytes
  Serial0.begin(115200);
  Serial0.setDebugOutput(true);
  while (!Serial) delay(100);
  neopixelWrite(RGB_BUILTIN, 0, RGB_BRIGHTNESS, 0);  // Green
  Serial0.println("Starting... run the Python Script.");
  delay(2000);
}

#define CONFIG_PREFIX_LENGTH 1500
void loop() {
  byte pre[CONFIG_PREFIX_LENGTH];

  size_t prefixLength = Serial.readBytes((byte *) pre, 1500);
  if (prefixLength > 0) {
    Serial0.println(prefixLength);
  }
}

Python running on a Windows 11 computer:

import serial

print ("CDC App test for issue 10000")

try:
	# CDC same as SERIAL_8N1 - Arduino equivalent
	# Change 'com15' to what ever is your USB CDC serial device name (win/linux)
	# timeout=None means that it will work as a blocking read()
	# write() is blocking by default

	CDC = serial.Serial(port='com15', baudrate=115200, parity=serial.PARITY_NONE,
	stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS, timeout=None) 
except:
	print("COM15: port is busy or unavailable")
	exit()

# Configure Serial Out and In as necessary using UART and/or CDC with respective config in the sketch

count = 1
chars_100 = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUV"

while 1:
	# writes 100 bytes in blocking mode
	for x in range(count):
		CDC.write(chars_100.encode('utf_8'))
	print("#"+str(count * 100)+" bytes sent!")
	count = count + 1
	if (count > 50):
		count = 1

---

Findings:

No issue after running it for more than 3 hours, non stop. Throughput is about 45,000 bytes per second (or 360Kps).
Problems found when Power Plan from Windows Control Panel has timeout for Blanking the Screen or for Suspending Activities.
In that case I found out that S3 doesn't reset, but the PC stops transmission.

In order to make it work with no failure, I has to set both (blanking screen/ suspend activities0 to "Never".
Using a Linux computer that is not necessary as the Python script runs in background forever.

[SuGlider]

@sblantipodi - The sketch and script from #10000 (comment)
has been running for almost 24 hours. No issue so far.

Both, PC and S3 are communicating using USB. No disconnection.
I think that the issue isn't in the Arduino/USB side.
I may be in the windows/linux application side.

[sblantipodi]

@sblantipodi - The sketch and script from #10000 (comment)
has been running for almost 24 hours. No issue so far.

Both, PC and S3 are communicating using USB. No disconnection.
I think that the issue isn't in the Arduino/USB side.
I may be in the windows/linux application side.

@SuGlider that sketch lacks the WiFi connectivity part.
Please, just connect It to WiFi and test It again.
I'll do the same and report it.
I really appreciate what you are doing. Thanks.

[SuGlider]

Please, just connect It to WiFi and test It again.

No issues again.

// using S3 devKit - RGB LED will indicate that CDC has been
// open by Python Script.
// If S3 resets, Python script will hang/fail and LED will be kept RED

// Serial is the USB port - Enable CDC on Boot!
// Serial0 is the UART0 - Console -- Serial Monitor

#include <WiFi.h>
#include <WiFiMulti.h>
#include <HTTPClient.h>

WiFiMulti wifiMulti;

void setup() {
  neopixelWrite(RGB_BUILTIN, RGB_BRIGHTNESS, 0, 0);  // Red

  Serial.begin();
  Serial.setRxBufferSize(1500);
  Serial.setTimeout(10); // reduces the time waiting for receiving bytes

  wifiMulti.addAP("SSID", "PWD");
  Serial0.begin(115200);
  Serial0.setDebugOutput(true);

  Serial0.println("Connecting Wifi...");
  Serial0.println();
  while (wifiMulti.run() != WL_CONNECTED) {
    Serial0.print(".");
    delay(100);
  }
  Serial0.println();

  if (wifiMulti.run() == WL_CONNECTED) {
    Serial0.println("");
    Serial0.println("WiFi connected");
    Serial0.println("IP address: ");
    Serial0.println(WiFi.localIP());
  }

  HTTPClient http;
  // testing connection...
  Serial0.print("[HTTP] begin...\n");
  http.begin("http://google.com/index.html");  //HTTP

  Serial0.print("[HTTP] GET...\n");
  // start connection and send HTTP header
  int httpCode = http.GET();

  // httpCode will be negative on error
  if (httpCode > 0) {
    // HTTP header has been send and Server response header has been handled
    Serial0.printf("[HTTP] GET... code: %d\n", httpCode);

    // file found at server
    if (httpCode == HTTP_CODE_OK) {
      String payload = http.getString();
      Serial0.println(payload);
    }
  } else {
    Serial0.printf("[HTTP] GET... failed, error: %s\n", http.errorToString(httpCode).c_str());
  }

  http.end();

  Serial0.println("Starting... run the Python Script.");
  while (!Serial) delay(100);
  neopixelWrite(RGB_BUILTIN, 0, RGB_BRIGHTNESS, 0);  // Green
}

#define CONFIG_PREFIX_LENGTH 1500
uint32_t count = 0;
void loop() {
  byte pre[CONFIG_PREFIX_LENGTH];
  if (wifiMulti.run() != WL_CONNECTED) {
    Serial0.println(".|");
    return;
  }
  size_t prefixLength = Serial.readBytes((byte *) pre, 1500);
  if (prefixLength > 0) {
    Serial0.println(prefixLength);
  }
}

[SuGlider]

@sblantipodi - I think that the problem may be in the application... some problem with lack of RAM?
A failed malloc() or no space for a String to allocate memory....

[sblantipodi]

@SuGlider can I ask you why you use Serial for read and Serial0 for write?
I can't read Serial0, how am I supposed to read Serial0?

The sketch that crashes on me, uses Serial for both read/write.

[SuGlider]

USB Serial can read by the Python Script, is necessary. The Windows COM port is open by this script.
I use Serial0 as console and open that with the Arduino Serial Monitor.

With reagards to reading and writing from USB Serial, there is a caveat that has to do with TinyUSB / HW Serial JTAG driver and the related tasks used to populate/consume the RX/TX Buffers. The Arduino Sketch runs in a very low Task priority. The USB Tasks run on a very high priority. This may cause some problems.