Why i cant use keypad 3x4 in nanoframework?

[sajjadarashhh]

I use key matrix feature and wana to connect and read user inputs from key pad 3x4
But that not working!!!!
I copy codes from document and connect each c and r cables to my board equals to pictures in document
Anyone do this?

[Ellerbach]

Can you please point out the technical documentation of your keyboard, ideally the schema used. And also the code you're using.
Usual trap with keypad: they have to use a pullup, so did you setup this properly?

[sajjadarashhh]

Wait i send you them

[sajjadarashhh]

I use it
But i dont know how to link and connect that to esp32 and how can i get a details from that in nanoframework

[sajjadarashhh]

@Ellerbach i see some documentation for this in key matrix but that not working with it.

[Ellerbach]

Do you have setu the pool up for each pin?

[sajjadarashhh]

What do you meaning for pool up?
I connect each pin equal to thats document to the esp board gpio pins like d1 d13 and...

[Ellerbach]

To be more precise, you have to use a hardware pull up for all input pins. See the diagram from the readme: https://github.com/nanoframework/nanoFramework.IoT.Device/blob/develop/devices/KeyMatrix/README.md#connection-using-on-board-gpio

You have resistors that needs to be used as a pull up

[sajjadarashhh]

Yes i tried that but thats not working 😑
I dont know why!
Wait i send to you thats picture howni connected

[Ellerbach]

There is no picture, it did not upload properly:

[sajjadarashhh]

This is a that two image i said
But idont know why this is not working when i wana use with c1: 13, c2: 27 c3:26
R1: 25, R2: 33, R3: 32, R4: 35

[josesimoes]

Something wrong with the images you've uploaded... please double check.

[sajjadarashhh]

Now check this
@josesimoes

[Ellerbach]

Seems like you are missing the pull ups.

[sajjadarashhh]

@Ellerbach what is the pull ups?

[Ellerbach]

See form this image: https://github.com/nanoframework/nanoFramework.IoT.Device/blob/develop/devices/KeyMatrix/4x4kb.png

There are resitors, if you don't have them, the input value won't be correct.

See here for the theory: https://en.wikipedia.org/wiki/Pull-up_resistor