Wireless temperature sensors - Prototypes
Now I have a few prototypes ready and working. It took me a while. I ran into a problem when connecting a USB Moteino to my server. It works OK in Windows, but I needed it connected to the Linux running in VirtualBox. The problem is that the Moteino USB did not reveal itself as a /dev/ttyUSB0. It turned up as a /dev/ttyS0.
Due to this fact I was unable to read the serial data from the Moteino. As I understand the /dev/ttyS0 is used by the terminal and is not directly readable as a serial device. I spent quite a few days to try to get this to work, to no avail. When connecting a Moteino trough a FTDI adapter, everything works as expected and it turns up as /dev/ttyUSB0.
I think I just have to cut the DTR connection on the board and solder the RTS connection. I'll try this later. I placed one of the sensor nodes in the bedroom and the other one in the entrance.
The base station
As of now I have just connected the receiving Moteino to the server. I will build in both the nodes and the receiver in appropriate enclosures. The nodes send out the following data to the receiver:
- RSSI (received signal strength indicator)
- Temperature (in celsius)
- Uptime (in seconds)
- Battery voltage (in mV)
- Radio temperature (in celsius)
The received data is processed by a Perl script and uploaded to Thingspeak.
I'm considering logging more info from the nodes, but as of now I have the ones mentioned.
Next part - Outside temperature sensor