Sorry if didn't make my previous message clear... Currently you can not use UART driver ('uart_driver_install') and standard IO, specifically input (fscanf, scanf) on the same UART peripheral. UART driver will try to read characters from UART peripheral. Standard IO library will also try to read cha...

Currently the UART driver can not be used together with console IO on the same UART. Both will try to read from UART FIFO, and only one (either console input or UART driver) will get any given character.

standard input on UARTs currently behaves as O_NONBLOCK; i.e. fgetc will return immediately, even if there is no data in UART FIFO. Does that explain the behaviour you are seeing? If not, could you describe "inconsistent" in more detail?

We don't use Quad SPI mode for loading the 2nd stage bootloader image, it is limited to DIO. So this shouldn't be an issue.

You need to configure all the pads in EFUSE, even if you are changing just one of them. Also note that WP pin can not be configured via EFUSE (not sure why it was left out). Becasue of this, for now, we support QIO mode only for ESP32-D2WD, where we know which pin is used for WP: https://github.com/...

In c++ you can still do

spi_device_interface_config_t devcfg={0};

and then set the fields you actually need.

There are a bunch of members in spi_device_interface_config_t structure which you aren't initializing, they include pre_cb and post_cb callback pointers. Because these pointers are not initialized, they contain garbage values previously present on the stack. SPI driver calls these function pointers ...

The getChipRevision function in Arduino has a bug, by the way, as it has "&& EFUSE_RD_CHIP_VER_RESERVE_V" instead of "& EFUSE_RD_CHIP_VER_RESERVE_V". Also, the 8-bit EFUSE_RD_CHIP_VER_RESERVE field is used to encode a bunch of different things. Lower 3 bits encode the package (0 = D0WDQ6, 1 = D0WDQ5...

Which pins are you using as SPI_MISO, SPI_MOSI, SPI_CLK?

You can use the following code for the TG0 timer: #include <stddef.h> #include "esp_intr_alloc.h" #include "esp_attr.h" #include "driver/timer.h" static intr_handle_t s_timer_handle; static void timer_isr(void* arg) { TIMERG0.int_clr_timers.t0 = 1; TIMERG0.hw_timer[0].config.alarm_en = 1; // your co...