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CelliesProjects / aquacontrol-hardware

Description and manual for aquacontrol hardware.
MIT License
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Transistor on LED 3v3 #2

Open danewber opened 5 years ago

danewber commented 5 years ago

I realize this isn't exactly an issue but can you provide some clarity on how you use a BC547 between pin 2 and the LED pin of the ILI9341? I've searched and searched for understanding to no avail.

danewber commented 5 years ago

I hooked up the ILI9341 with just a 330 ohm resistor between the LED and the screen because mine has a built in transistor. However, all I am getting is a dimmed backlight with no content on the screen. I've set the no miso to true to get it to detect since it wasn't.

danewber commented 5 years ago

I've found the issue to be the resistors. With no resistors the screen works fine except touch isn't functional. With the suggested resistors I get no output on the screen. Graphics demos also don't work properly. Now to figure out where I should be using resistors and what value. For reference, I'm using an esp-devkitc v4.

CelliesProjects commented 5 years ago

Probably you don't have enough power on the led pin. Maximum output from a esp32 pin is about 40mA which is too little for the backlights.