Error while reading barometric pressure sensor

Archives GrovePi
1

Hi why do i have this error? It is from barometric pressure sensor hp206c.

File “xxx.py”, line 55, in
temp=h.ReadTemperature()
AttributeError: ‘str’ object has no attribute ‘ReadTemperature’

Thank you.

2

Please post your code.

Best to put three back quotes

```
around your code

```

(The error message is telling that “h” was not properly initialized to be a sensor class object.)

Perhaps include all the output before the error also - and what is output when you try running the high_accuracy_barometer_example.py program

3

Hi

The code you gave was working fine till i add dht11 code and error came out.

Can you help to show how to combine dht11 and barometric pressure sensor codes?

thank yo

4

Please post your code and the console output.

5 
from __future__ import print_function
import paho.mqtt.publish as publish
import time
import hp206c
import psutil
import string
import random
import grovepi
import math
from time import sleep

h= hp206c.hp206c()
ret=h.isAvailable()

sensor = 7

blue = 0
blue = 1

string.alphanum='1234567890avcdefghijklmnopqrstuvwxyzxABCDEFGHIJKLMNOPQRSTUVWXYZ'
channelID = "xxx"
writeAPIKey = "xx"
mqttHost = "mqtt.thingspeak.com"
mqttUsername = "xx
mqttAPIKey ="xx"
tTransport = "websockets"
tPort = 80
topic = "channels/" + channelID + "/publish/" + writeAPIKey

if h.OK_HP20X_DEV == ret:
 print("HP20x_dev is available.")
else:
 print("HP20x_dev isn't available.")

while True:
        try:


                [temp,humidity] = grovepi.dht(sensor,blue)
                if math.isnan(temp) == False and math.isnan(humidity) == False:
                    print("temp = %.02f C humidity =%.02f%%"%(temp, humidity))
                sleep(1)

		temp=h.ReadTemperature()
                pressure=h.ReadPressure()
                altitude=h.ReadAltitude()



                print("Temperature\t: %.2f C\nPressure\t: %.2f hPa\nAltitude\t: %.2f m" %(temp,pressure,altitude))
                time.sleep(5)

                #Prep connection to Thingspeak
                clientID=''
                # Create a random clientID.
                for x in range(1,16):
                        clientID+=random.choice(string.alphanum)



                t = str(temp)
                p = str(pressure)
                a = str(altitude)
#                t1 = str(temp)
                h  = str(humidity)

                        # build the payload string for Thingspeak
                payload =  "field1=" + t + "&field=2" + h + "&field3=" + p + "&field4=" + a

                        # attempt to publish data to the topic on Teamspeak.
                try:

                        publish.single(topic, payload, hostname=mqttHost, transport=tTransport, port=tPort,auth={'username':mqttUsername,'password':mqttAPIKey})
                        print (" Published to host: " , mqttHost , " clientID= " , clientID)

                except (KeyboardInterrupt):
                        break

	        except:
                        print ("There was an error while publishing the data.")


                time.sleep(5)

        except (IOError,TypeError) as e:
                print("Error")
6

pi@raspberrypi:~ $ python 1.py
HP20x_dev is available.
Temperature : 26.68 C
Pressure : 999.26 hPa
Altitude : 117.11 m
Published to host: mqtt.thingspeak.com clientID= k4ufsEyLe4O0Bs5
Traceback (most recent call last):
File “1.py”, line 44, in
temp=h.ReadTemperature()
AttributeError: ‘str’ object has no attribute ‘ReadTemperature’

7

You already have used h for the sensor, make this “hum” or “strHumidity”

8

Hi

It doesn’t work even with pressure or altitude
Traceback (most recent call last):
File “1.py”, line 45, in
Pressure=h.ReadPressure()
AttributeError: ‘str’ object has no attribute ‘ReadPressure’

9

Did you change the line: h = str(humidity) ???

strHumidity = str(humidity) 
# build the payload string for Thingspeak 
payload = "field1=" + t + "&field2=" + strHumidity + "&field3=" + p + "&field4=" + a

(Note the error you had field=2 should be field2= No?)

h starts out as your hp206c sensor:

h= hp206c.hp206c()

then later you are assigning a string to h:

h = str(humidity)

then the loop repeats and you try to read the hp206c sensor using “h” but it no longer contains the sensor, you overwrote a string into “h”, so when you try to get temp from the sensor, it tells you that you have confused it.

10

Hi thanks , no error now but dht11 not updating in thingspeak. hp206c did update

‘’’
while True:
try:

            air_quality = grovepi.analogRead(Airquality)
            light_intensity = grovepi.analogRead(LightSensor)
            sound_level = grovepi.analogRead(SoundSensor)


            if sound_level > 0:
                    last_sound=sound_level



            [temp,humidity] = grovepi.dht(sensor,blue)
            if math.isnan(temp) == False and math.isnan(humidity) == False:
                print("temp = %.02f C humidity =%.02f%%"%(temp, humidity))
            sleep(1)

            temphp206c=h.ReadTemperature()
            pressure=h.ReadPressure()
            altitude=h.ReadAltitude()


      thp = str(temphp206c)
            p = str(pressure)
            a = str(altitude)
            t = str(temp)
            hum  = str(humidity)
            aq = str(air_quality)
            l = str(light_intensity) 
            s = str(last_sound)


                    # build the payload string for Thingspeak
            payload =  "field1=" + t + "&field=2" + hum + "&field3=" + p + "&field4=" + a + "&field5=" + aq + "&field6=" + s + "&field7=" +l + "&field8=" + thp

‘’’

11

@RobertLucian please mark this one solved.

@azizahsham I think you can and should figure out Thingspeak yourself. We got your GrovePi reading the sensors; up to you to decide what to do with the data.