Bridge pins like a virtual switch or keypad?

Hello, I’m new to the Arduino world and have come here for some guidance. So, hoping someone here can tell me if the Arduino can do what I need it to do. I’m updating a vending machine so we can put a credit card reader on it. The last problem is the keypad. If both keypads were the same matrix 3x4 I wouldn’t be here. The new keypad is a simple 3x4 but the old one is a 5x5 that only uses 12 of the 25 buttons. So, I have been able to hook up the old keypad to the Arduino and have the buttons programmed but now I need to have to Arduino send out the correct button pushed to the controller. The old key pad had letters and the new keypad uses numbers not that that matters but for the ease of explaining when I press the “A” button I then need the Arduino to act like I pushed the “1” button. I metered the keypad wires from the controller and I have 1.5v on pin 2 and GND on pin 1. When I short 1 & 2 I get “1” on the controller. So, that’s my issue or question. Can the Arduino act like a virtual keypad?? If so is there a program already made to do this?? Or can someone point me in the right direction?? Thanks.

Can You imagine that sharing the old code and the new wiring could be useful for helpers?

Yes, please share your work.

Show us a good schematic of your circuit.
Show us a good image of your ‘actual’ wiring.
Give links to components.


In the Arduino IDE, use Ctrl T or CMD T to format your code then copy the complete sketch.
Use the </> icon from the ‘reply menu’ to attach the copied sketch.

!

Here are pics of the old and new keypads. As you can see the new keypad is a different form factor. I don’t have any drawn schematics yet. Not sure there is going to be much in the way of wiring as I have the old keypad plugged directly into the Arduino and I’m hoping I can plug the controller directly into the Arduino.

Sorry I can only put 1 pic in a post but here is the new keypad.

Yes. You can use analog switches or analog selectors to connect any of the five ROW pins to any of the five COLUMN pins.

https://www.analog.com/en/parametricsearch/10624#/p4683=(8:1)%20x%201&sort=4683,desc

You will need 7 data pins. Each of the selectors will have three address pins and an enable pin. The two enable pins can be connected to the same output. Turn off the enables, set the ROW address and COLUMN address pins, and turn on the enable to 'close the switch' at that row and column.