LCD display doesnt show values fore temperature and humidity
grosscha...@serrahs.com
I'm trying to finish my self-water plant system. https://www.hackster.io/demirhanaydin/waterpi-houseplant-remote-watering-and-monitoring-system-340400?ref=platform&ref_id=424_respected___&offset=33. I'm on the final stages but I'm unable to get my LCD screen to display my temperature and sensor values. I'm running sudo node index.js and this is what happens.
The raspberry pi connects and the Arduino is registered. The temperature and humidity are also registered. Then i get
fs.js:663
return binding.writeBuffer(fd, buffer, offset, length, position);
Error: Unknown system error -121: Unkown system error -121, write
Then i have about 10 errors
at Error (native)
at Object.fs.writeSync (fs.js:663:20)
at Bus.i2cWriteSync (/home/pi/waterpi-node_modules/raspi-io/node_modules/raspi-i2c/node_modules/i2c-bus/i2cbus.js:348:13
at I2c.writeSync (/home/pi/waterpi-node/node_modules/raspi-io/node_modules /raspi-i2c/dist/index.js:307:37
at RaspiIOcore.i2cWrite (/home/pi/waterpi-node/node_modules/johnny-five/lib/lcd.js:64:11
at LCD.Controllers.PCF8574.initialize.value (/home/pi/waterpi-node/node_modules/johnny-five/lib/lcd.js:362:23
at new LCD (/home/pi/waterpi-node/node_modules/johnny-five/lib/lcd.js:783:1-
at Boards .<anonymous> (/home/pi/waterpi-node/index.js:60:9
at emit0ne (events.js:77:13)
I know that my LCD works and is being registered by my raspberry pi because I have checked using i2cdetect. I also ran a simple hello world code using python.I tried changing the controller name of the lcd to PCF574A nothing changed . If anyone could help it would be appreciated.
Ben Noordhuis
I2C communication issues. Sometimes you can glean more information
from the syslog.