Stepper Motor

A function generator to run a uni-polar stepper motor such as the tiny BYJ-48 from a Raspberry Pi. Note that you'll need some kind of buffer module/chip as the Pi can't supply sufficient current to a stepper motor.

Inputs "Step" and "Direction" message types and 4 outputs for the motor pins. If you pass a value of 10 when you send a step message then the outputs will cycle through 10 steps. Use the delay node to control the rate of motor stepping.

The "LED" function nodes use the status indicator so you can see what's happening without having to hook it up to GPIOs

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count < steps; count++) { \n    outputMsgs.push({payload:1});\n}\nreturn [ outputMsgs ];","outputs":1,"noerr":0,"x":434,"y":90,"wires":[["637b5925.225a28"]]},{"id":"637b5925.225a28","type":"delay","z":"97192799.714bd","name":"","pauseType":"rate","timeout":"5","timeoutUnits":"seconds","rate":"2","rateUnits":"second","randomFirst":"1","randomLast":"5","randomUnits":"seconds","drop":false,"x":615,"y":76,"wires":[["b833a444.b121f8"]]},{"id":"19a25cb3.2752a3","type":"inject","z":"3db945ee.2c881a","name":"Step","topic":"Step","payload":"1","payloadType":"num","repeat":"","crontab":"","once":false,"x":330,"y":185,"wires":[["52c41dde.2b7024"]]},{"id":"e3a75e9a.2abe28","type":"inject","z":"3db945ee.2c881a","name":"Direction","topic":"Direction","payload":"1","payloadType":"num","repeat":"","crontab":"","once":false,"x":333,"y":240,"wires":[["52c41dde.2b7024"]]},{"id":"52c41dde.2b7024","type":"subflow:97192799.714bd","z":"3db945ee.2c881a","name":"","x":623,"y":207.5,"wires":[["6bf4aed4.02b14"],["e1f7bd52.ebfb18"],["f4d3178.cd67e68"],["63bd4a0b.8bc31c"],["43c248eb.08c858"]]},{"id":"75ecccf0.7a940c","type":"debug","z":"3db945ee.2c881a","name":"1","active":false,"console":"false","complete":"payload","x":1023,"y":78.5,"wires":[]},{"id":"5e4f7f85.05023","type":"debug","z":"3db945ee.2c881a","name":"2","active":false,"console":"false","complete":"payload","x":1028,"y":147.5,"wires":[]},{"id":"700a200f.68175","type":"debug","z":"3db945ee.2c881a","name":"3","active":false,"console":"false","complete":"payload","x":1032,"y":202.5,"wires":[]},{"id":"4e3bc2c6.bef53c","type":"debug","z":"3db945ee.2c881a","name":"4","active":false,"console":"false","complete":"payload","x":1032,"y":270.5,"wires":[]},{"id":"43c248eb.08c858","type":"debug","z":"3db945ee.2c881a","name":"Motor Debug","active":false,"console":"false","complete":"true","x":858,"y":350,"wires":[]},{"id":"123c7681.19d5f1","type":"inject","z":"3db945ee.2c881a","name":"Multistep","topic":"Step","payload":"10","payloadType":"num","repeat":"","crontab":"","once":false,"x":319,"y":125,"wires":[["52c41dde.2b7024"]]},{"id":"6bf4aed4.02b14","type":"function","z":"3db945ee.2c881a","name":"Green LED","func":"if (msg.payload == 1)\n    node.status({fill:\"green\",shape:\"dot\",text:\"LED On\"});\nelse\n    node.status({fill:\"green\",shape:\"ring\",text:\"LED Off\"});\nreturn msg;","outputs":1,"noerr":0,"x":878,"y":79,"wires":[["75ecccf0.7a940c"]]},{"id":"e1f7bd52.ebfb18","type":"function","z":"3db945ee.2c881a","name":"Green LED","func":"if (msg.payload == 1)\n    node.status({fill:\"green\",shape:\"dot\",text:\"LED On\"});\nelse\n    node.status({fill:\"green\",shape:\"ring\",text:\"LED Off\"});\nreturn msg;","outputs":1,"noerr":0,"x":870,"y":145,"wires":[["5e4f7f85.05023"]]},{"id":"f4d3178.cd67e68","type":"function","z":"3db945ee.2c881a","name":"Green LED","func":"if (msg.payload == 1)\n    node.status({fill:\"green\",shape:\"dot\",text:\"LED On\"});\nelse\n    node.status({fill:\"green\",shape:\"ring\",text:\"LED Off\"});\nreturn msg;","outputs":1,"noerr":0,"x":867,"y":204,"wires":[["700a200f.68175"]]},{"id":"63bd4a0b.8bc31c","type":"function","z":"3db945ee.2c881a","name":"Green LED","func":"if (msg.payload == 1)\n    node.status({fill:\"green\",shape:\"dot\",text:\"LED On\"});\nelse\n    node.status({fill:\"green\",shape:\"ring\",text:\"LED Off\"});\nreturn msg;","outputs":1,"noerr":0,"x":864,"y":274,"wires":[["4e3bc2c6.bef53c"]]}]

Flow Info

Created 8 years, 9 months ago
Updated 6 years ago
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Node Types

Core
  • comment (x1)
  • debug (x5)
  • delay (x1)
  • function (x7)
  • inject (x3)
  • switch (x1)
Other
  • subflow (x1)
  • subflow:97192799.714bd (x1)

Tags

  • motor
  • stepper
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