Saw another topic here about brightness control on the
3.5" TFT Featherwing mod gone wrong. I was very hesitant to attempt the mod because of that topic. However, I've come to learn that he did it incorrectly which was probably the cause of his issue.
Wire a jumper from the LITE pad to pin D2. Success!
- TFT_Featherwing_LITE_Mod.jpg (92.35 KiB) Viewed 91 times
Don't be afraid. I just did it successfully and only 1 simple jumper wire is needed. The mod is unobtrusively permanent with no problems using stacking feathers on top of it. Use pin D2 as the PWM pin, most featherwings (including the tft featherwing) don't use it in the SPI bus so it's a good free pin candidate to use.
My camera darkens the surrounding background while at full brightness. It's super bright.
- Full_Brightness.png (665.69 KiB) Viewed 88 times
The picture doesn't do it justice for how dim it actually is. I can barely see it but the camera picks it up fine.
- Dimmed_Display.png (648.38 KiB) Viewed 88 times
Place this code anywhere in your code.py. Control the brightness with display_duty_cycle from 0 (off) to 65000 (100% bright).
Code: Select all
import pwmio
display_duty_cycle = 10000 # Brightness Values from 0 to 65000
brightness = pwmio.PWMOut(
board.D2,
frequency=500,
duty_cycle=display_duty_cycle)
The frequency should always be 500 for this particular TFT.
I just want to document this because I was put off from doing the modification due to reading the other forum topic not going well.
Happy to report it works great!
