- Mon Jun 22, 2015 1:51 pm
#21258
The bootloader of interest is in the first page of flash. Espressif provides updates to it in its SDK distributions in the bin directory. It has logic to select the correct partition to support OTA update. The firmware image format contains the flash parameters (size, speed) in a few header bytes. I assume the bootloader starts with a lowest-common-denominator setting until it can read these header bytes. At least this is what I've gathered thus far.
- Mon Jun 22, 2015 4:22 pm
#21278
first stage is in processor ROM?
see here: http://richard.burtons.org/2015/05/17/e ... t-process/
see here: http://richard.burtons.org/2015/05/17/e ... t-process/
- Mon Jun 22, 2015 4:28 pm
#21280
It is not what people said, the internal ROM is located at 40000000h
https://github.com/esp8266/esp8266-wiki/wiki/Memory-Map
and also from viewtopic.php?f=5&t=9&start=30#p274 :
https://github.com/esp8266/esp8266-wiki/wiki/Memory-Map
and also from viewtopic.php?f=5&t=9&start=30#p274 :
0x40000000 (64K) - ESP8266 builtin ROM. It appears to be truly builtin, as its content doesn't appear in external FlashROM dump. The ROM technology is unclear. It can be mask ROM, or OTP, or just flash ROM whose means of programming are yet to be discovered. As more dumps for different modules will be collected, we'll be able to differentiate these choices.
