Hi!
I want to replace individual buttons connected to DIN module with a slim 20-button pad which is organized in 4x5 lines.
Looks like DIO_Matrix module support matrix connections, but according to schematic it require diodes.
But 20 button pad has already connected lines without diodes.
Any ideas?
Since no one has responded to this, I thought I would at least add my thoughts.
You can use this keypad without diodes but there will be some problems if you push 2 or more buttons at the same time. True this isn’t a normal use of the keypad but finger checks do happen. To protect against having 2 of the CMOS output ports shorted together when 2 or more keys are push simultaneously, I would just put a 220 ohm resistor in series with each of the output lines going to the 74hc595 chip. This will protect the hardware.
Pete Knobloch
