Hello, sorry for my bad English, but it is not my native language and I do not speak it well. I come to the forum because I need help, I can't get a matrix keyboard to work (8 columns x 2 rows, in the future it will be 16 columns and 3 rows) in conjunction with a CD74HC4067 multiplexer. I am using…

[Sin título-1] Sorry, I don't know how to make electrical diagrams, with their symbols and technicalities. That's why I attach a drawing (pretty bad really, I apologize for that too), but I hope it can be useful.

You have 16 buttons and a 16:1 multiplexer. Why add the complexity of a diode matrix circuit?

[image] mr_robertron_x7: int SetMuxChannel(byte channel){ digitalWrite(muxS0, bitRead(channel, 0)); digitalWrite(muxS1, bitRead(channel, 1)); digitalWrite(muxS2, bitRead(channel, 2)); digitalWrite(muxS3, bitRead(channel, 3)); } byte c8 = SetMuxChannel(8); 'SetMuxChannel()' does …

[image] anon57585045: You have 16 buttons and a 16:1 multiplexer. Why add the complexity of a diode matrix circuit? hello, first of all thank you for your help and comments :). answering your question. I really need a number of buttons of 16x3, but I am using 8x2, to understand the programm…

Your code is part traditional matrix and has some guesses it looks like about how to do a matrix keyboard with multiplexers. Fortunately your friend google can help out, as this problem has been so,fed many times. For now, google multiplexer matrix keyboard and poke around. When I'm back at the …

OK this [image] Is an Arduino fast enough for monitoring these lines? Too fast? General Guidance Hi I am interested in connecting an Arduino to an old Science Fair Microcomputer Trainer. This is mainly as a learning exercise for me on both platforms. The SFMT…

[image] mr_robertron_x7: I will expand the number of buttons to what I really need, that is the reason. What is that number?

[image] anon57585045: What is that number? 16 x 3 = 48, additionally I need some pins for some encoders, screens and 2 joysticks, so it is almost mandatory to learn how to use a multiplexer and matrices.

Why? Most key switch arrays like keyboards don't use a multiplexer. If you want to minimize Arduino pins, the standard way is to use shift register IC's, or dedicated I/O expander IC's.

Help with CD74HC4067 on matrix keyboard

Projects Programming

anon57585045 August 2, 2022, 5:59pm 19

Bypass the amateur hacky stuff. Download some service manuals of synth keyboards. Check out this recent thread
https://forum.arduino.cc/t/keyboard-matrix-74hc138/1018597

Topic		Replies	Views
My midi keyboard project is failing, i think it has something to do with the code Programming	4	122	February 17, 2026
MIDI keyboard with 2 Multiplexer General Guidance	45	6386	August 4, 2022
I need help with my arduino midi project Programming	4	84	February 15, 2026
4X4 Keypad with multiplexer Programming	15	652	January 17, 2025
Keyboard Matrix Reduce I/O LEDs and Multiplexing	23	9947	November 9, 2014

Help with CD74HC4067 on matrix keyboard

Related topics