78 lines
2.1 KiB
Markdown
78 lines
2.1 KiB
Markdown
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# Voting Machine
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### ~ avatar
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Build a vote collection system using many micro:bit!
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### ~
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https://youtu.be/77HOqf8BaNg
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In this project, a **voter** program is uploaded on the player's @boardname@. The player uses the buttons to vote yes or no
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and the vote sent to the **dashboard** @boardname@ via radio. The dashboard allocates one LED per player and turns it on for "yes" and off for "no".
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Both programs set their radio group to ``4`` to be able to communicate.
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## The voter program
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Assuming button ``A`` is no and ``B`` is yes, the voter program works as follows:
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* when button ``A`` is pressed, a number ``0`` is sent via radio and the ``X`` symbol is shown on the screen.
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```block
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input.onButtonPressed(Button.A, () => {
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radio.sendNumber(0)
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basic.showIcon(IconNames.No)
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})
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```
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* when button ``B`` is pressed, a number ``255`` is sent via radio and the ``Y`` symbol is shown on the screen.
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```block
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input.onButtonPressed(Button.B, () => {
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radio.sendNumber(255)
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basic.showIcon(IconNames.Yes)
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})
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```
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* In order to track the votes, we tell the radio to also transmit the device serial number.
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```block
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radio.setTransmitSerialNumber(true)
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```
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* we arbritrarily choose ``4`` as the group used for the communications
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```block
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radio.setGroup(4)
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```
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Combined together, the voter program looks as follows:
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```blocks
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input.onButtonPressed(Button.A, () => {
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radio.sendNumber(0)
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basic.showIcon(IconNames.No)
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})
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input.onButtonPressed(Button.B, () => {
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radio.sendNumber(255)
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basic.showIcon(IconNames.Yes)
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})
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radio.setGroup(4)
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radio.setTransmitSerialNumber(true)
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basic.showIcon(IconNames.Ghost)
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```
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## The dashboard
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The dashboard code can be found at [/examples/radio-dashboard](/examples/radio-dashboard).
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Download the code from that example into the @boardname@ that will be used to display the result.
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When the dashboard receives a message from a @boardname@, it find a pixel for that board (and remembers it)
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and uses the number received as the brightness of the LED.
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When a message hasn't been received by a board for some time, it's pixel will start to blink. After more time, it will simply turn off.
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