Re: Effect of lengh of wires in matrix


roxlu wrote:
Hi,

I've created a small prototype where I connected 64 tiny dip-switches
in a matrix of 8x8. Using a
serial in shift register and a serial out shift register I'm scanning
through these buttons to check which one is pressed. This works
perfectly.

Now I'm gonna buy a lot more and bigger buttons (33mm, 256 pieces). The
matrix will be approximately 100cm x 100cm. As I'm not very experienced
in electronics I'm curious how this will afffect the workings of my
circuit.

I'm using a PIC16f628 for the scanning and I'm communication with a PC
using RS-232.


Sounds like a good design. My money is on it working just fine. There
is a built-in lag in reading via the shift registers.

Luhan


Luhan

.