hef4067 question

Hi at all, i'm newbe to Arduino. I have a little problem and a little confusion :astonished: for controlling 16 switches and send a serial command with an Arduino Mega 2560 and an HEF4067BP. The example code for normal use with normal I/O is that , but i have a problem whith th expansion of digital output using a demultiplexer solution. Thanks at all for a little hand!!

if (pinNo == 23 && pinStateSTR == "0"){Serial.println ("C19");} if (pinNo == 24 && pinStateSTR == "0"){Serial.println ("C18");} if (pinNo == 25 && pinStateSTR == "0"){Serial.println ("C14");}

There is no link to the hardware datasheet, no wiring diagram to understand how that hardware is connected to the Arduino and the code is only a minimal excerpt which doesn't contain any hint about what you're trying to do. Provide the necessary information!

but i have a problem whith th expansion of digital output using a demultiplexer solution.

May we ask you to tell us your problem?