Native USB CDC hangs up on ESP32-S2 after about 320 characters

[technoblogy]

Board

Adafruit QT-Py ESP32-S2

Device Description

Plain board.

Hardware Configuration

No.

Version

v2.0.2

IDE Name

Arduino IDE

Operating System

macOS 10.13.6

Flash frequency

80MHz

PSRAM enabled

yes

Upload speed

921600

Description

Entering text into the Serial Monitor causes the Serial to hang up after about 320 characters. Run the following sketch, then cut and paste all the following text (total 512 characters) into the Serial Monitor input field, and press Return:

$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ

The Serial Monitor prints:

64
128
192
256
320

ie it hangs up after 320 characters and doesn't reach 512.

NB I've implemented the patch suggested by @SuGlider from PR #6133 in Issue #6205.

Sketch

void setup() {  
  Serial.begin(9600);
}

int Count = 0;

void loop (void) {
  if (Serial.available()) {
    Serial.read(); Count++;
    if (Count % 64 == 0) Serial.println(Count);
  }
}

Debug Message

No debug output.

Other Steps to Reproduce

Also tested on UM FeatherS2 - hangs up in the same way.

Works fine on ESP32-C3 DevKit and Adafruit ESP32 Feather.

I've tried adding Serial.setRxBufferSize(1024) but has no effect.

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

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

[SuGlider]

@technoblogy
I have tested it with ESP32, ESP32-C3 and ESP32-S2 (Saola) - using the latest Github version (git checkout master).
I've tested it with 300, 4800, 9600, 38400, 57600, 115200 and 230400 baud.
All of them reached 512.

Could you test it with the complete latest Arduino Core Version?

Please let me know.
Thanks!

Results with ESP-ROM version information - using 115200 baud for reading the boot messages

ESP-ROM:esp32s2-rc4-20191025
Build:Oct 25 2019
rst:0x1 (POWERON),boot:0x8 (SPI_FAST_FLASH_BOOT)
SPIWP:0xee
mode:DIO, clock div:1
load:0x3ffe6100,len:0x510
load:0x4004c000,len:0xa50
load:0x40050000,len:0x28bc
entry 0x4004c18c
64
128
192
256
320
384
448
512

[technoblogy]

Could you test it with the complete latest Arduino Core Version?

@SuGlider I'm not quite sure how to do this. If I download arduino-esp32-master it's not in a form that I can put in /library/Arduino15/packages. Can you point me to some instructions?

[SuGlider]

@technoblogy
You can add a new set of ESP boards from github.
Follow this instructions

This is how it will look like:

You shall see ESP32 Arduino (in sketchbook) in the Menu-->Tools-->Board.

[technoblogy]

I installed from the development link:

https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_dev_index.json

Is that correct? It still seems to be version 2.0.2.

[SuGlider]

@technoblogy
The idea is to create a folder under your regular sketch Arduino, i.e. ~/Arduino/hardware/espressif/esp32 and clone the current repository into this folder.

These are the commands for Linux:

cd <Your Arduino Sketch folder>
mkdir hardware
cd hardware
mkdir espressif
cd espressif
git clone --recursive https://github.com/espressif/arduino-esp32 esp32

After cloning the master branch into esp32, it is necessary to run esp32/tools/get.py (or get.exe for Windows).
Then restart your Arduino IDE and you will see the new board ESP32 Arduino (in sketchbook) in the Board Menu.
Open it and select your ESP32 board. This will compile to the lastest ESP32 GitHub version.

To update the GitHub in you computer, just go to the esp32 folder in <Your Arduino Sketch folder>/hardware/espressif/esp32 and run git pull. No need to run get.py again - run it once, in the first time.

[technoblogy]

Thanks - I'll try it.

[technoblogy]

@SuGlider I followed your instructions which worked without error, but when I try to compile I get:

fork/exec /Users/david/Documents/Arduino/hardware/espressif/esp32/tools/xtensa-esp32-elf/bin/xtensa-esp32-elf-g++: no such file or directory

I can see that file, but it's in the path:

/Users/david/Documents/Arduino/hardware/espressif/xtensa-esp32-elf/bin/xtensa-esp32-elf-g++

[SuGlider]

Did you also run get.py?