Was looking at building an ODB2 HUD using Freematics ESP32 OBD Kit connected to the Sparkfun Transparent OLED HUD.
Looking at the code I cant see any dimming options for the display which I think it would need for night viewing.
Does anyone know if it has a way of dimming?
Thanks
Hi 12hak and thanks for your post!
It might be possible to dim this display but unfortunately we don’t have the data to know for sure if it can be, and if it is possible, how it would be done. Wish we had a better answer for you but I was unable to locate anything that said one way or another.
Thats a bit crytic 
Who is the developer of the Sparkfun code? They must have some details on the programming options?
The developer of the code is our founder and he sits behind me in the office. Unfortunately there is no function we’re aware of that enables changing the brightness of segments in the display and we don’t have a data sheet for the display itself to see if a function exists. The best I’ve been able to find is [this datasheet but it doesn’t mention anything about the ability to dim the display.
The only thing I can think of that might work to change the display brightness would be to vary the 12 volt power going to the display or possibly PWM the 12 volt rail but I don’t know if that will work with the display and our driver board wasn’t designed to allow for that.](https://cdn.sparkfun.com/assets/c/0/b/c/e/LD7138-Revision_1.0__2_.pdf)