MicroPython Forum (Archive)

I have an ESP32 (TTGO T8) monitoring my vegetable garden. I left the cover off its enclosure last night and it rained. This morning the code had crashed and I was unable to get REPL access via USB. I hooked up a serial connection and still cannot get Rshell to connect. When I use ESPTool, I get the following:

“Detecting chip type... ESP32
Chip is ESP32-D0WDQ6 (revision 1)
Features: WiFi, BT, Dual Core, 240MHz, VRef calibration in efuse, Coding Scheme None
Crystal is 40MHz”

Followed by the error:

“WARNING: Failed to communicate with the flash chip, read/write operations will fail. Try checking the chip connections or removing any other hardware connected to IOs”

The flash chip is a BY25Q32BSSIG (32MBIT SPI NOR FLASH SOP8 208mil) and it is easily accessible because this board doesn’t have a shield.

Do you guys think replacing this chip will fix it?
I couldn’t find an exact replacement but I found a 64MBIT version with the same pinout and package. Can I just swap in the bigger one?

I'd wave a hair-dryer over it for awhile before trying to replace a chip. Check for any sign of corrosion between the pins on the flash IC.

Good luck!

davef wrote: ↑

Sat May 21, 2022 5:02 am

I'd wave a hair-dryer over it for awhile before trying to replace a chip. Check for any sign of corrosion between the pins on the flash IC.

I should have mentioned I already cleaned the board with MG Super Wash and I reflowed all the components.

Doesn't the ESP32 chip have a metal shield over it?

davef wrote: ↑

Sat May 21, 2022 5:37 am

Doesn't the ESP32 chip have a metal shield over it?

Not all ESP32 boards have the board level shield. The TTGO T8 doesn't have one. The lack of shield will make it easier to replace the flash chip although a metal cover may have prevented the damage in the first place.

I can't help with expereince but there are a number of comments in esp-idf code and docs about chip support. you might want to double check the docs/ code in that component to be sure they have support for your proposed chips.

This has some references to sizes above 32Mb for example:
https://docs.espressif.com/projects/esp ... flash.html

Looking through components/spi_flash/* there's some officially supported chips and a generic driver which they say covers most chips.

marcidy wrote: ↑

Sat May 21, 2022 4:32 pm

I can't help with expereince but there are a number of comments in esp-idf code and docs about chip support. you might want to double check the docs/ code in that component to be sure they have support for your proposed chips.

This has some references to sizes above 32Mb for example:
https://docs.espressif.com/projects/esp ... flash.html

Looking through components/spi_flash/* there's some officially supported chips and a generic driver which they say covers most chips.

Thanks that's very helpful especially the supported chips.