ESP.restart() does not always reset ESP32.

[sblantipodi]

Hardware:

Board: ESP32 from D32 board from Lolin
Core Installation version: 1.0.6
IDE name: Platformio (platform-espressif32 v.3.2.1)
LIB Used: no libs
Flash Frequency: 40Mhz
PSRAM enabled: no
Upload Speed: 460800
Computer OS: Windows 10 and Ubuntu

Description:

ESP.restart() does not always reset ESP32.
Sometimes it seems that it reset but then it does not boot and I need to manually use the reset button to make the ESP start again.

[TD-er]

What is connected to GPIO-0?

[sblantipodi]

@TD-er nothing. it seems that the problem happen if I write something to storage using LittleFS.

if (SPIFFS.begin()) {
    // SPIFFS.format();
    File configFile = SPIFFS.open("/" + filename, "w");
    if (!configFile) {
      helper.smartPrintln("Failed to open [" + filename + "] file for writing");
    }
    serializeJsonPretty(jsonDoc, Serial);
    serializeJson(jsonDoc, configFile);
    configFile.close();
    helper.smartPrintln("[" + filename + "] written correctly");
  } else {
    helper.smartPrintln(F("Failed to mount FS for write"));
  }
ESP.restart()

this code writes well things into Little FS but hangs ESP32 at the restart point.
ESP32 is restarted but then it does not boot until I manually press the reboot button.

[TD-er]

And if you close the filesystem first before calling the ESP.restart() ?

[lbernstone]

As TD-er said, try closing the FS, and even putting a flush before you close the configFile.
Other thing to check (again along the lines of what TD-er said) is the strapping pins. If there is a device or a capacitor on one of those pins, it can affect the boot sequence such that it will not start. You can see the state in the boot log. Note that ESP.restart() aka esp_restart() is not equivalent to a cold boot. abort() is a more complete system reset if that won't damage your startup flow (at least it will tell you if the restart is getting hung up rather than the boot).

[sblantipodi]

@TD-er it seems that it doesn't help.

@lbernstone should I try abort()
ESP.abort() does not exist. how can I try abort()?

[sblantipodi]

latest IDF solved my problem