DAY3 intern in Deutschland : Radio signal
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Today we continue to focus on communication but via wireless(Radio signal and Bluetooth)
How far radio signal in Calliope can go?
Once we want to know range of radio signal in Calliope, how far they can go. That is to say, we cannot find this information on the internet.
So, we programmed Calliope to send signal to others by pressing A button. If it send, RGB LED will bright blue. If it receive signal RGB LED will turn to red and have sound like “Peep”.
Used 2 Calliope in this experiment, we gradually step backward from each other while pressing the button until there is one of us cannot hear sound. We have to say that range of Calliope’s radio signal is around 20 meters but not sure because there is wall and corner at the end of aisle, I think it’s effect to signal.
They’re talking to each other
Next, I programmed Calliope to send signal to the others by itself.
All of them already has same code: They will random 1–10 seconds to send signal after received from the others, Except setting group(I will explain it in next subtopic). I assigned 2 different groups: As you can see in the picture 2 Calliopes on left side is in group 0 and another one is in group 1.
Grouping
Calliope can communicate with other calliope via radio module and exchange information among themselves by indicating the group. The radio signal is sent by broadcasting. The signal will be received by all other Calliopes that assign in the same group using ‘set group’ block(Possibly 0 to 100). If we don’t set the group, every calliopes will receive the signal.
In case that we assigned groups, the first 8 bits of the signal indicates the group. If we want to send the signal to specific calliope, we have to write the code in separate cases. The calliope can also communicate with the micro:bit by using the radio signal.
