Stefans Lab Notes
Interesting Bits and Pieces
http://armdevs.com/WiFiG25.html Atmel G25-based small board, like the Arietta G25, but with an USB WiFi module already integrated, and with 256MB flash onboard
PL9823 Programmable RGB LEDs
Everybody loves the WS2812B, but sometimes, you need a classic 5mm LED. Adafruit's NeoPixel apparently is a PL9823 (datasheet), availablable at some AliExpress stores and at LED Genial. Also Soldering Sunday, Cool Components.
ESP8266 WiFi Controller Module
Links to sources:
- Espressif official forum, including SDK download
- ESP8266.com user forum: module versions
- esptool.py to upload firmware to the controller through it's bootloader
- Collection of firmware, SDKs, etc.
There seems to be little consolidated information, so here's my experiences so far.
The bootloader is not protected; overwriting the bootloader with a non-functioning version will brick the module.
To get the boot loader into firmware update mode, GPIO0 must be pulled low to GND, GPIO2 must be left floating. (For the module to work at all, CH_PD [chip power-down] must be pulled high.)
ElectroDragon Wi07c AT Command Firmware
The ElectroDragon firmware for the Wi07c mode can be programmed like this:
$ esptool.py --port /dev/cu.usbserial write_flash 0x00000 Electrodragon-V0925/eagle.app.v6.flash.bin $ esptool.py --port /dev/cu.usbserial write_flash 0x40000 Electrodragon-V0925/eagle.app.v6.irom0text.bin
Note that the command given on their page lists the load address for the irom0 part as 0x4000 which is wrong, it must be 0x40000.
Then you can connect to the serial at 9600 to issue AT commands. Note that the firmware requires LF (ctrl-J) after each command, not CR (Ctrl-M or the return key).
Sprite's Web Server Firmware
This post has a link to precompiled binaries; I managed to flash them successfully like this:
$ ~/working/esp8266/esptool/esptool.py --port /dev/cu.usbserial write_flash 0x00000 0x00000.bin $ ~/working/esp8266/esptool/esptool.py --port /dev/cu.usbserial write_flash 0x40000 0x40000.bin $ ~/working/esp8266/esptool/esptool.py --port /dev/cu.usbserial write_flash 0x12000 webpages.espfs
~/working/esp8266/esptool/esptool.py --port /dev/cu.usbserial write_flash 0x00000 ~/working/nodemcu-firmware/0.9.2/512k-flash/nodemcu_512k.bin
Serial console at 9600 let's you enter LUA commands. The commands appear to be quite comprehensive.