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Can I replace a >32Mbit SPI flash on ESP8266 module?

Posted: Tue Oct 10, 2017 4:34 pm
by water
I want to replace a >32Mbit SPI flash(e.g W25Q128) on ESP8266 module with ISP bus connected,not HSPI external, is it work?
the normal firmware v1.9.2 is support it ?
how biggest size of SPI flash supported on ESP8266 ?

Re: Can I replace a >32Mbit SPI flash on ESP8266 module?

Posted: Tue Oct 10, 2017 6:18 pm
by Roberthh
You can replace the 32MBit (4 MByte) flash on an esp866 with an 128Mbit (16MByte). I did that, end technically it worked. However, the ESP8266 firmware does not use the memory beyond 4 MByte, and the code must not grow beyond 1 MByte. You could use that for storage, using the flash primitives of the esp module. I had the plan to modify flashbdev.py to use the full physical memory. It must however skip a few pages at the 4 MByte border, since that is used by the ESP firmware. Then the file system would have a size of about 15 MByte. But until now this was not really needed.

Re: Can I replace a >32Mbit SPI flash on ESP8266 module?

Posted: Wed Oct 11, 2017 10:14 am
by water
Roberthh wrote:... ... I had the plan to modify flashbdev.py to use the full physical memory.
concern.

:idea: