This is a demo code for I2C LCD (AIP31068) for the ESP32S3 ULP RiscV using software I2C.
The simple code drives the I2C 16x2 LCD (usually sold as Grove 16x2 LCD) with the AIP31068 controller on the ESP32-S3's RiscV ULP.
The code has been tested on Cytron's Maker Feather AIOT S3.
The hardware I2C for the ULP is not accessible on this board (see page 479 and 480 on ESP32-S3 Technical Reference Manual), software I2C is used.
Software I2C routines by PascalPolygon: STM32 Software I2C, modified for the RiscV ULP.
Since the ULP's RTC GPIO is only coupled up to GPIO 21, the example is using GPIO 4 and 7 instead.
After programming the board, press Reset button to run the ULP program.
References:
Note: For Cytron's Maker Feather AIOT S3 users using this SDK, please enable the GPIO11 first if you need to use the diagnostic LEDs on board!