Home brew firmware for the ESP8266 based 303 WIFI LC 01 clock.
I did a first analysis of the board. Find my findings in subdirectory 1-pcbnets.
The goals is to make our firmware and flash that on the board. I made a backup of the original firmware, see subdirectory 2-fwbackup, just in case.
This proves that we can communicate with the internal bootloader, so that we can also upload our own firmware.
With the backup made, let's see if we can flash our own firmware, see subdirectore 3-flash.
The firmware illuminated unexpected segments. Time to analyze the display, see subdirectory 4-display.
With the board reverse engineered, it is time to write my own firmware. A basic NTP clock, see subdirectory 5-clock.
The NTP clock form the previous section already has a configuration option in EEPROM, e.g. for the WiFi AP to connect to. However, I also want the clock to show whose birthday it is today. Maintaining a list of birthdays via the EEPROM is too clumsy. So I decided to check if the ESP can read a Google docs spreadsheet. Here is a proof of concept 6-webcfg.
The final firmware is a clock that shows upcoming birthdays, see 7-bdays.
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