I flashed the ESP-12E from AT firmware 2.0 (running ok) to NodeMCU (running ok). When I reflashed it back to the AT 2.0 it is stuck in endless loop on boot:
ets Jan 8 2013,rst cause:2, boot mode:(3,6) load 0x40100000, len 2408, room 16 tail 8 chksum 0xe5 load 0x3ffe8000, len 776, room 0 tail 8 chksum 0x84 load 0x3ffe8310, len 632, room 0 tail 8 chksum 0xd8 csum 0xd8 2nd boot version : 1.6 SPI Speed : 40MHz SPI Mode : QIO SPI Flash Size & Map: 8Mbit(512KB+512KB) no GPIO select! jump to run user1 @ 1000 rf_cal !=0x05,is 0xFF
I am sure I flashed it correctly, it was not my first flashing of AT firmware. Just to be sure:
esp_init_data_default.bin -> 0x3fc000 blank.bin -> 0x3fe000 boot_v1.6.bin -> 0x0000 user1.1024.new.2.bin -> 0x1000 blank.bin -> 0x7e000
I can even reflash it to the NodeMCU firmware and it works, but reflashing to the AT firmware ends in the same endless loop again.
I suspect the problem is in initialization data, but I'm at my wit's end with it.