Keyboard with Analog input

Projects Programming
1

Hi. I'd like to use a matrix keyboard with analog input with various resistences on analog pin 5
I have this matrix with resistence values

380 416 446 475 1 2 3 A
534 555 757 590 4 5 6 B
628 642 656 665 7 8 9 C
693 704 711 720 * 0 # D

Of course I have to consider the possibility that resistor give me some varations (5%) so I have some intervals

There's some script I can modify to get this working?
I didnt found anyting and i'm not so expert to male it alone
Thank you

2

Of course I have to consider the possibility that resistor give me some varations (5%) so I have some intervals

So, a 5% variation will occur on the values read from the analog pin, too.

446 + 5% = 446 + 22.3 = 468.3
475 - 5% = 475 - 23.7 = 451.3

So, what does a reading of 460 mean?

3

I grab this values reading them with the first analog imput example of arduino uno. the real variation is about 5 units...
But the question is...How can I use this?? I need some code

4

Can you clarify exactly how this matrix is wired?

5

Like this but i have 180ohm resistor not 200 and i found only 5% tollerance...