i am working on a project using a 20x4 sainsmart lcd2004 screen. i am using an arduino uno. i have wired vcc to 5v, connected the ground, wired the sda pin to a4 and scl to a5. i am using the address 3f, 20, 4. my screen has power and the contrast is good but there are no characters appearing on the screen and the boxes are very light. i need help with this. thanks
Try looking at some of the myriad of posts in this forum section dealing with I2C display adapters.
The fact that you are using a particular display is irrelevant, it is the I2C adapter that you must identify if you want help.
Don