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Detecting if T43 display module is physically connected to EMX


how can I detect if T43 display module is physically connected to EMX?
I am using a custom PCB with EMX 4.2


Just to clarify.

Do you mean How can you detect that a T43 display is connected as apposed to another display(e.g. T35 or other display) ? Or do you just need to detect if any display is connected?

If you have a custom PCB there are probably a few ways to detect that ‘any’ gadgeteer display is connected. You could for instance use one of the VCC lines on the sockets as a sense input rather than a voltage output. The remaining 2(3 if using the T socket) should still be able to provide enough current.

I can’t think of a way of detecting the type of display connected other than user feedback.


It us not designed to be detected as it is either always there or not! However, you may try the backlight pin with pull up our pull down and see if you can detect it that way.


I just need to detect if T43 is connected. As my device can b used without display, but I have a lot of code running for display issues. Dont want to run all those codes if the user didnt connect the display module , which will be useless.
I will try your suggestions.


@ denizalp - Use an IO pin(input port) as a display option selector. Use an internal pullup resistor. Ground for display, or let go high for no display. You just need a way to setup a jumper for selecting the option.