ESP32 Forum

Hi,everyone, I bought ESP32D2WD a few days ago,but i cant use it correctly even if refer to the references and resources.so i need your help.Is there any hardware schematic about ESP32D2WD or any test board which i can buy? here is the schematic i use,is there any question ?(ps:the spi flash is empty,and the power is on.)

Best wishes! Daniels.

I'm not actually sure that we have a reference schematic for ESP32D2WD, however it should be identical to ESP32D0WD with only the following differences:

- Embedded flash is connected internally to pins GPIO16, GPIO17, SD_CMD, SD_CLK, SD_DATA_0 and SD_DATA_1. So ensure none of these pins are connected externally. (Ref: ESP32 datasheet Section 2.2 Pin Descriptions, Note at bottom)

- SD_DATA_2 & SD_DATA_3 (GPIOs 9 & 10) are not used for internal flash on ESP32-D2WD and can be used as GPIOs if required.

The schematic image you posted is a little small to clearly read all the GPIO numbers, but if you check it against the ESP32D0WD reference designs with the above two caveats in mind, you should be OK.

If you've checked the design and are you still having problems with the board, can you please describe them? Have you verified all power ground/pins are correctly powered, CH_PD (EN) pin is pulled high, and that the crystal is oscillating? If all these are true, you should at least get some UART serial output and can continue debugging from there.

Gpio16 shows it is being used for charged signal. As stated it is already used by internal flash and also all sdio group gpio are operating at 1.8v.

thanks ESP_Angus and WiFive,it is you who give me the direction.As the ESP_Angus 's answer,I know the Gpio16 should not be used for others. so i have make it float,but it does not work! I noticed that the VDD_SDIO pin is always 0 V no matter what the MTDI pin 's voltage is. Is this normal? sorry for Reply so late,because I've tried three times.So I expect your answer very much.
Best wishes.Daniel.

Do you have uart connected? Is there any output?

thanks your reply.@ WiFive,yes,I have uart connected,There is nothing output.That makes me very helpless.

Daniel wrote:I have uart connected,There is nothing output.That makes me very helpless.

OK, in this case the good news is that it's not the flash or anything specific to the ESP32D2WD variant. If it was the flash, you'd at least get some kind of error on the UART. My earlier post had the things to check in this case:

Have you verified all power ground/pins are correctly powered, CH_PD (EN) pin is pulled high, and that the crystal is oscillating? If all these are true, you should at least get some UART serial output and can continue debugging from there.