Got some new NodeMCU modules: Wemos D1. Very neat small modules with USB and “shields”, one of them being a 0.66″ I²C OLED display with 64×48 pixel. Very cute.
I needed some extra NodeMCU modules (specifically 1-wire and u8g), so a new firmware was in order. Best place for that is http://nodemcu-build.com/. Highly recommended.
One odd problem I saw though: when using the usual
./esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash 0x0 ~/Downloads/nodemcu-master-20-modules-2016-08-13-01-27-33-integer.bin
to program the FLASH, all I got is a stream of data on the serial port after a reset and not the usual prompt. Power cycle did not change that behavior. Neither did waiting. Even re-programming esp_data_init_default.bin did not help. What did help is adding the -fm and -fs parameters:
./esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash -fm dio -fs 32m 0x0 ~/Downloads/nodemcu-master-20-modules-2016-08-13-01-27-33-integer.bin
The interesting bit is that programming an older image from about a month ago worked fine without -fm and -fs. Which made me think there’s something buggy in the creation of the image (e.g. the new modules I added are broken).