Let's now start sending the commands from MQTT.fx client and see our car in motion.
To move forward, we publish the message forward on topic controlPi/cmd as shown in Figure 8.12.
Command:
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On the Subscribe tab we will see the message move forward as acknowledgment sent back from the car as a confirmation that the car is moving forward now. Refer to the following screenshot:
Acknowledgment:
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To move backward/reverse we publish command reverse; the car will start moving in a backward direction, the red LED will glow and on the Subscribe tab we will see the message move reverse.
Command:
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Acknowledgment:
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To make a right turn Publish message right; the car will make a right turn and the right side indicator will blink. On the Subscribe tab we will receive the message Turn Right.
Command:
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Acknowledgment...