My system consists of two XBee S1
s and a Raspberry Pi
. I've attached a TMP36
sensor and a LDR
to the first XBee S1
and transmit those infromations to the second XBee S1
via the ZigBee protocol. The second Xbee S1
is connected via USB adapter to the Raspberry Pi
. My first XBee S1
is powered by batteris at 5V.
As the voltage given by the batteries decreases over time, I would like to have an indeication of the voltage supplied by the batteris in order to know when I should change them. Can you tell me how can I do that? My idea is to make a gauge with 4 LEDs
attached to the Raspberry Pi. The problem I am facing is that I do not know how can I send the supply voltage via the Xbees(as the XBee 1 itself is powered by that battery).
PS: I don't want to use a multimeter every time I am wondering how much voltage is provided by the batteries.