The nano satellite will talk on RS-232 9600 baud and since I'm
programming the PIC MCU I can make up my own protocol.
I'm thinking something like:
Groundstation sends this: ?Temperature1
And the satellite then replies: !Temperature1[Data]EndofData
I will have 10 different probes in the satellite, monitoring currents,
voltages and temperatures and I need some help and tips on how to
filter the incomming string and split it up so that I can route the
approrpriate data to the appropriate frontpanel? or graph.
If you let the satelite send a ASCII telegram of comma separated
floating point numbers (one float for each measured parameter) for
example every second. You will have to predefine the number of
parameters and in wich order they are sendt. After the last parameter
you can add a checksum to varify the received telegram. End the
telegram with a carriage return and linefeed.
Satelite ID,CH1,Ch2,...,CHn,ChkSumCRLF
In your serial read vi, you can detect the CRLF and convert the
telegram into an array of floats.
This is a common way of sending data from dataloggers. If you don't
want to use a predefined update rate, you can poll the satelite and
use the same sort of telegram as the answer. This way you don't need
to worry about the identification of the measured parameters.
Erik
