Thank you for pointing me to the right file. That was indeed very helpful and solved the problem by introducing my own panic_print_char() function.

Is there a way to get the currently active SPI flash mode from inside the app?

The SPI mode (40/80 MHz, DOUT/QIO and so on) is compiled into the bootloader and also the app. Is that right? I wonder if it is somehow possible to first boot into a fail-safe mode (40 MHz, DOUT) and later switch to the fastest possible mode. Let's say of the devices in the field some are capable of...

Same problem:
https://www.esp32.com/viewtopic.php?f=2&t=26144

ESP32 rev0 on TTGO, using IDF 4.4.1. Compiled with -Os parameter (important). #include <string.h> #include "driver/rmt.h" #include "nvs_flash.h" void app_main(void) { rmt_config_t tx = { .channel = RMT_CHANNEL_0, .gpio_num = 20, .mem_block_num = 1, .clk_div = 40, .tx_config.idle_output_en = true, .r...

Minimum code example: #include "esp_log.h" #include "esp_wifi.h" #include "nvs_flash.h" #include "mdns.h" static const char *TAG = "main"; void app_main(void) { nvs_flash_init(); esp_netif_init(); esp_event_loop_create_default(); esp_netif_create_default_wifi_sta(); wifi_init_config_t wifi_init_conf...

The correct order to call the functions is: mdns_init mdns_hostname_set mdns_instance_name_set mdns_service_add When we call them like this: mdns_init mdns_service_add mdns_hostname_set mdns_instance_name_set The IDF crashes with a LoadProhibited. And it costs hours to find out the wrong order is th...

Is there a way to get ets_install_putc1() operational in the ESP32 IDF?

Example code. Run it and leave it for 1-3 days. It will (soft-)restart automatically every hour. Use PuTTY or a similar terminal and do not hardware reset the chip during the test. The problem will only manifest after several hours or days. Typical output see below. #include "esp_log.h" #include "es...