AT328p-au GPIO pins multiplexing

[ejazbeyond]

i want to know if a can multiplex gpio pins. i have to add air quality sensor, in my device but MCU dont have GPIOs left. Please recommend solution.

 

[Nigel Goodwin]

Yes of course you can multiplex I/O pins, it's a standard technique going back to the very early days of micro-processors.

 

[ejazbeyond]

i am using at328p-au. i only have one gpio left and i have to use air quality sensor. so data can be send using multiplexing.air quality sensor

 

[Pommie]

Can you list what you currently have on your i/o pins?

Mike.

 

[Nigel Goodwin]

As Pommie, says, it all depends on what the other pins are doing, you may well be able to better utilise what you've got.

Even if you can't, you can't multiplex a single pin, you need multiple pins to feed the multiplexer/port expander - so you would need to move some of your existing I/O's to the multiplexed connections.