Stepper Motor

README.md

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

flow.json

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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"]]}]

Hi, I'm also having problems with the delay of the motor (28BYJ-48). The steps are successfully sent to motor and the LEDs on my ULN2003 stepper are in sequence, but it is just far too slow. I'm running on a Raspi B (rev1) with node-red server running. Delay node in stepper motor sub-flow from 1ms to 100ms or 1000ms all too slow.

Python script running on the pi with a delay of 1ms spins at expected rate, but the NodeRed just doesn't seem to deliver fast enough.

Anybody had a decent output to a stepper? Node-red too slow on a pi or should I be looking elsewhere.

Anybody tried python functions in node-red python function blocks? Thanks