This was indeed a soldering issue on the chip near the VDD_SDIO pin. Reworking the chip soldering around that pin seems to have gotten me past this issue.

I have created a board with ESP32-PICO-D4 and am facing an issue with continuous rebooting with the following block... rst:0x10 (RTCWDT_RTC_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) configsip: 188777542, SPIWP:0xee clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 mode:DIO, clock ...

Is there any way to increase the clock out amplitude as I suspect that to be the problem?

The lan8720 needs a clock to do anything, not sure why there is no output on gpio0 for you Yes. I can confirm that on the same setup the config fails when I simply disable the 50MHz clock. I checked again with an oscilloscope with GPIO0 open (disconnected from LAN8720) and i can see that ~50MHz clo...

Is there anyway to debug this? I would like to avoid the extra pin to enable the oscillator and the cost of the oscillator itself. Hence, I would like to use GPIO0_OUT. GPIO16 and GPIO17 are unavailable on PICO-D4.

Does the 50MHz clock have any relation to configuring the lan8720? Why does register setup fail when I disconnect the oscillator? I can see the clock on the scl line.

Just to be sure, I checked out release/v3.2 and switched the compiler to recommended version (5.2) but the problem is the same.

WiFive wrote: ↑

Sun Jun 16, 2019 2:48 pm

Which esp-idf version do you use?

git master.
$ git describe
v4.0-dev-837-g58df1d93b

I'm testing ethernet with the ESP32-PICO-KIT + Waveshare LAN8720 module. I got ethernet working as per https://sautter.com/blog/ethernet-on-esp32-using-lan8720/ but I now want to use GPIO0 as clock output instead of input. To achieve this, I removed R12 and R14 resistors on the waveshare board and j...

Also interested in this. Bridging between ETH, STA and AP.