Multiple RPISER devices

grovepi
gps
co2

#1

I have two Grove devices I want to connect to the RPISER port, the Grove CO2 sensor and the Grove GPS sensor. Can I simply user a grove splitter cable to connect them both to the same port?


#2

Hi @raymond.romoth,

I’m afraid you can’t do this since these 2 devices start broadcasting on the serial line at the same time - and there’s no synchronization happening on the RPISER line.

A workaround would be to use a digital selector. The idea is to connect the TX lines of these 2 sensors to a digital selector.
The digital selector is supposed to have an output that lets the signal of one of the two inputs pass depending on a selector input called X.

You can google "1 bit digital selector" and take a look at the images you find - they’re descriptive.

Thank you!


#3

Thanks for the tip. I’ll have a look around and see what I can find. If I can’t get the digital selector to work I might see if I can find a digital CO2 sensor. Any suggestions?

Thanks again


#4

Hi @raymond.romoth,

The following sensor could be a good alternative. It’s from Sparkfun:


I encourage you to read more about it. You can use it along with a GrovePi just fine.

Also, you can connect the sensor via the GPIO ports of the GrovePi.
As for soldering a Grove connector on the Sparkfun module instead, that’s going to be a bit tricky, but it could work eventually.

Thank you!


#5

Cool. Thanks for finding an alternative sensor. I’ll definitely check it
out if I can’t get the digital selector thing working.

Ray