Using Keypad Matrix with RA8875 (Eastrising models)

As promised I provided library to support the 5x4 keypad matrix scanner inside RA8875
Only some boards has PIN exposed for using a Keypad, the Eastrising boards have a dedicated connector.
Before all you have to enable this feature on the board, by default all Eastrising cards have the following jumper pads shorted:

• J1
• J2
• J3
• J4
• J5

You have to open all of them.

Next, there's 5 SMD resistor to solder (accordly Estrising Datasheet), they ask for 5x100K, BUT!
During my test I discovered that 100K it's not the right value, the pullup it's too weak and I got a lot of garbage. Instead I've used 5x10K and worked well.
YOU DON'T NEED TO SOLDER RESISTORS ON BOARD, if you are not able to do that you can use a much easier alternative!
You can solder common troughole resistor between each input to 3V3, they are just needed for pullups!

In brief here's wiring:

Eastrising Keypad connector:

• 1: Ki0 -> keypad line 0 (plus a 10K resistor to 3V3) [matrix input]
• 2: Ki1 -> keypad line 1 (plus a 10K resistor to 3V3) [matrix input]
• 3: Ki2 -> keypad line 2 (plus a 10K resistor to 3V3) [matrix input]
• 4: Ki3 -> keypad line 3 (plus a 10K resistor to 3V3) [matrix input]
• 5: Ki4 -> keypad line 4 (plus a 10K resistor to 3V3) [matrix input]
• 6: Ko0 -> keypad row 0 [matrix output]
• 7: Ko1 -> keypad row 1 [matrix output]
• 8: Ko2 -> keypad row 2 [matrix output]
• 9: Ko3 -> keypad row 3 [matrix output]

Frequently asked questions:

• Q:If I leaved jumper J1..J5 and decide to NOT use the keypad it will interfere with normal TFT operation?
• R:NO, It works as before.
• Q:I decided to use a smaller matrix, there's drawbacks?
• R:In that case you must leave the 10K pullup resistor connected to the unused matrix line or you get garbage!

To be continued: (soon the software setup and options for using interrupt pin)