ESP8266 Community Forum

- Sat Mar 05, 2016 10:53 am #42485

Effectively, but SD-D1 is required to access the flash in both DIO and QIO mode. The only way to free up the pin would be that have the flash in SIO (single i/o with SD-D0), which I doubt we can.

Thanks for that info.
(To that: is the external flash memory needed, or does the chip have some onboard mem, and if how much?)

I think I will have to read a lot more about the flash interface (and the chip as a whole)
Can you point me to some good reading for that, apart from the obvious (datasheet, Espressiv-HP, here) ?

- Sat Mar 05, 2016 12:06 pm #42489 Unfortunately, the ESP doesn't have any internal Flash, so all firmwares are located in the external one. Without this Flash, ESP cannot boot at all.