Error 121 - GrovePi+ LCD RGB Backlight Temperature Sensor DHT11

Products & Technology
1

I’m having Error 121 problem.
Currently I am using :

  • Raspberry Pi 4 Model B (Linux raspberrypi 5.10.17-v7l+ #1403 SMP Mon Feb 22 11:33:35 GMT 2021 armv7l GNU/Linux)
  • GrovePi+ HAT (updated as of 7th March 2021)
  • Grove LCD RGB Backlight v4.0
  • Temperature Humidity Sensor v1.2

Getting error 121

Please help.

import math
import datetime
import grovepi
from grove_rgb_lcd import *

try:
    setRGB(255,255,255)
    setText("Initializing...")
    
    time.sleep(2)
    
    sensor = 4
    blue = 0
    
    while True:
        try:
            [temp,humidity] = grovepi.dht(sensor,blue)
            mytxt = "T = {}C H = {}% ";
            if math.isnan(temp) == False and math.isnan(humidity) == False:
                nnow = datetime.datetime.now().strftime("%X")
                setText_norefresh(mytxt.format(temp,humidity) + nnow)
                print(mytxt.format(temp,humidity) + nnow)
            time.sleep(1)
        except IOError as io_error:
            print("io_error = " + str(io_error))
            raise IOError
    
    
except KeyboardInterrupt:
    setRGB(0,0,255)
    setText("Exit OK")
except IOError as ioerror:
    print(ioerror)
    setRGB(255,0,0)
    setText("IO Error")

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