WS03 (WS01 WS05) LED Controller - stodev-com-br/Tasmota GitHub Wiki
The WS01 LED-Controller uses an ESP8266-S1 Module (16MBit Flash) Alle required Pins for programming are available, as well as additional GPIO4 and GPIO2.
GPIO2 & GPIO4 are working for I2C (2=SDA 4=SCL). (Tested with DS3231 Module ) The device uses an additional CD4050 at the pins used for PWM.