Hello,
- from your description I’m not sure if your board is a dev board NUCLEO-F334R8 | Mbed or a custom board with same MCU.
- F334R8 has only 64 KB Flash and 12 KB SRAM, so I think it still possible to use it with MbedOS 5.15.7 but under Bare metal profile becasue it is low memory target, for full MbedOS.
- do not forgot to use pull-up resistors for both wires of I2C, if are not already implemented somewhere!
- with displays usually needs to set up a contrast, with bad settings you will see nothing
- what is good to do, is verified your I2C connection by this simple example code that will return an address if the conenction is OK
- I use this TextLCD and also this useful guide about all things around it
- also take care about correct setting in TextLCD_Config.h
- last, how is written on I2C API page, be sure about correct address format
Note: The Arm Mbed API uses 8 bit addresses, so make sure to left-shift 7 bit addresses by 1 bit before passing them
.
BR, Jan