I am working on a project and I wish to have multiple MQ-X type sensors working on a Raspberry Pi 4. I have an order of 10 different gas sensors arriving, all with both analog and digital (TTL) output. Most important are the Methane, CO and H2S sensors.
It seems that the RPi has only 1 serial connection exposed through GPIO. I also have ordered a single USB-to-TTL adapter. Will I need to have 10x USB adapters? I thought I read that only 1 adapter works at a time, but correct me if I am wrong.
What would be the best approach to reading the TTL signal from all 10? Would I need a special microprocessor or an Arduino?
Thanks for any help!