Read an i2c-based mpu6050 accelerometer on a raspberry pi

README.md

Read accelerometer, gyro, and temperature data

One inject writes data to the i2c address and register of the mpu6050 device to configure it for reading.

The top inject button then can request 14 bytes from the same i2c address and formats the response data for display to the debugger.

flow.json

[{"id":"12867341.ed798d","type":"nodebot","name":"","username":"","password":"","boardType":"raspi-io","serialportName":"","connectionType":"local","mqttServer":"","pubTopic":"","subTopic":"","tcpHost":"","tcpPort":"","sparkId":"","sparkToken":"","beanId":"","impId":""},{"id":"a2a45691.5d5ba8","type":"gpio out","name":"","state":"I2C_READ_REQUEST","pin":"","i2cDelay":"0","i2cAddress":"104","i2cRegister":"59","outputs":1,"board":"12867341.ed798d","x":283,"y":694,"z":"fb26e0ad.04d92","wires":[["7058226d.8fa7dc"]]},{"id":"ed1b31d8.12e4d","type":"debug","name":"","active":true,"console":"false","complete":"false","x":500,"y":622,"z":"fb26e0ad.04d92","wires":[]},{"id":"7058226d.8fa7dc","type":"function","name":"process i2c","func":"var data = msg.payload;\nvar int16 = function(high, low) {\n  var result = (high << 8) | low;\n  // if highest bit is on, it is negative\n  return result >> 15 ? ((result ^ 0xFFFF) + 1) * -1 : result;\n};\n\n\nmsg.payload = {\n    accelerometer : {\n        x: int16(data[0], data[1]),\n        y: int16(data[2], data[3]),\n        z: int16(data[4], data[5])\n    },\n    temperature : int16(data[6], data[7]),\n    gyro : {\n        x: int16(data[8], data[9]),\n        y: int16(data[10], data[11]),\n        z: int16(data[12], data[13])\n    }\n};\n\nreturn msg;","outputs":1,"valid":true,"x":315,"y":548,"z":"fb26e0ad.04d92","wires":[["ed1b31d8.12e4d"]]},{"id":"970b8ad3.68f478","type":"inject","name":"","topic":"","payload":"14","payloadType":"string","repeat":"","crontab":"","once":false,"x":119,"y":552,"z":"fb26e0ad.04d92","wires":[["a2a45691.5d5ba8"]]},{"id":"7a2b3f6.f85d4c","type":"gpio out","name":"","state":"I2C_WRITE_REQUEST","pin":"","i2cDelay":"0","i2cAddress":"104","i2cRegister":"","outputs":0,"board":"12867341.ed798d","x":275,"y":790,"z":"fb26e0ad.04d92","wires":[]},{"id":"bd2a7e35.42d58","type":"inject","name":"","topic":"","payload":"","payloadType":"none","repeat":"","crontab":"","once":false,"x":90,"y":633,"z":"fb26e0ad.04d92","wires":[["c625f941.39da08"]]},{"id":"c625f941.39da08","type":"function","name":"i2c bytes","func":"msg.payload = [0x6B, 0x00];\nreturn msg;","outputs":1,"valid":true,"x":139,"y":709,"z":"fb26e0ad.04d92","wires":[["7a2b3f6.f85d4c"]]}]

Thanks for the flow, do you have any code to transform the raw data to m/^2, Celsius and º for the gyroscope??

Regards ...

I keep getting the following error after doing sudo su, then node-red start. Does raspi-io need to be installed within npm install node-red-contrib-gpio foder?

Started Node-RED graphical event wiring tool..
28 Mar 00:20:21 - [info]
Welcome to Node-RED

28 Mar 00:20:21 - [info] Node-RED version: v0.16.2
28 Mar 00:20:21 - [info] Node.js version: v6.10.1
28 Mar 00:20:21 - [info] Linux 4.4.50-v7+ arm LE
28 Mar 00:20:23 - [info] Loading palette nodes
pi : TTY=unknown ; PWD=/home/pi ; USER=root ; COMMAND=/usr/bin/python -u /usr/lib/node_modules/node-red/nodes/core/hardware/nrgpio.py info
pam_unix(sudo:session): session opened for user root by (uid=0)
pam_unix(sudo:session): session closed for user root
28 Mar 00:20:30 - [info] Dashboard version 2.3.6 started at /ui
28 Mar 00:20:37 - [info] Settings file : /home/pi/.node-red/settings.js
28 Mar 00:20:37 - [info] User directory : /home/pi/.node-red
28 Mar 00:20:37 - [info] Flows file : /home/pi/.node-red/flows_raspberrypi.json
28 Mar 00:20:37 - [info] Server now running at http://127.0.0.1:1880/
28 Mar 00:20:37 - [info] Starting flows
1490678437632 Device(s) RaspberryPi-IO
1490678437663 Device(s) RaspberryPi-IO
1490678437688 Device(s) RaspberryPi-IO
1490678437713 Device(s) RaspberryPi-IO
28 Mar 00:20:37 - [info] Started flows
28 Mar 00:20:37 - [red] Uncaught Exception:
28 Mar 00:20:37 - Error: EACCES: permission denied, open '/sys/class/leds/led0/trigger'
at Error (native)
at Object.fs.openSync (fs.js:641:18)
at Object.fs.writeFileSync (fs.js:1347:33)
at new LED (/home/pi/.node-red/node_modules/raspi-led/dist/index.js:42:18)
at RaspiIOCore.value (/home/pi/.node-red/node_modules/raspi-io-core/dist/index.js:525:34)
at RaspiIOCore.pinMode (/home/pi/.node-red/node_modules/raspi-io-core/dist/index.js:484:21)
at /home/pi/.node-red/node_modules/raspi-io-core/dist/index.js:408:17
at Array.forEach (native)
at /home/pi/.node-red/node_modules/raspi-io-core/dist/index.js:337:32
at _combinedTickCallback (internal/process/next_tick.js:73:7)
at process._tickDomainCallback (internal/process/next_tick.js:128:9)
nodered.service: main process exited, code=exited, status=1/FAILURE
Unit nodered.service entered failed state.
nodered.service holdoff time over, scheduling restart.
Stopping Node-RED graphical event wiring tool....
Starting Node-RED graphical event wiring tool....
Started Node-RED graphical event wiring tool..
28 Mar 00:20:40 - [info]

Dear,

Does anybody know where should be the problem with the error message:

Flows stopped due to missing node types.

nodebot

Thank you

same here, nodebot missing which seems to be the i2c IO, see pic