I used to display 0 - 3.3V by using MCP3008 and Pi. My sensors are 0 - 10V and I draw a circuit (picture below here) to divide voltage. According to my calculations it should work but it shows wrong. When sensor is 5V, I see 4,5V on the screen. And it should be 0 - 10V but after 8.8V it reach 1023. I dont understand what is problem. If someone has idea plase guys let me know.
The circuit
- circuit
- circuit.png (20.31 KiB) Viewed 738 times
Code: Select all
import spidev
import time
import os
import urllib
import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
spi = spidev.SpiDev()
spi.open(0,0)
def ReadChannel(channel):
adc = spi.xfer2([1,(8+channel)<<4,0])
data = ((adc[1]&3) << 8) + adc[2]
return data
def ConvertVolts(data,places):
volts = (data * 10) / float(1023)
volts = round(volts,places)
return volts
def ConvertTemp(data,places):
temp = ((data * 330)/float(1023))-50
temp = round(temp,places)
return temp
sensor1_channel = 0
sensor2_channel = 1
sensor3_channel = 2
sensor4_channel = 3
sensor5_channel = 4
sensor6_channel = 5
sensor7_channel = 6
sensor8_channel = 7
delay = 5
GPIO.setwarnings(False)
GPIO.setup(5, GPIO.IN)
GPIO.setup(6, GPIO.IN)
GPIO.setup(13, GPIO.IN)
GPIO.setup(19, GPIO.IN)
GPIO.setup(26, GPIO.IN)
GPIO.setup(16, GPIO.IN)
GPIO.setup(20, GPIO.IN)
GPIO.setup(21, GPIO.IN)
while True:
foldtime = time.time()
fnewtime = time.time()
fstore = 10.0 # second
while True:
fnewtime = time.time()
fdtime = fnewtime-foldtime
digital1 = GPIO.input(5)
digital2 = GPIO.input(6)
digital3 = GPIO.input(13)
digital4 = GPIO.input(19)
digital5 = GPIO.input(26)
digital6 = GPIO.input(21)
digital7 = GPIO.input(20)
digital8 = GPIO.input(16)
if digital1 == 1:
digital1 = 'ON'
else:
digital1 = 'OFF'
if digital2 == 1:
digital2 = 'ON'
else:
digital2 = 'OFF'
if digital3 == 1:
digital3 = 'ON'
else:
digital3 = 'OFF'
if digital4 == 1:
digital4 = 'ON'
else:
digital4 = 'OFF'
if digital5 == 1:
digital5 = 'ON'
else:
digital5 = 'OFF'
if digital6 == 1:
digital6 = 'ON'
else:
digital6 = 'OFF'
if digital7 == 1:
digital7 = 'ON'
else:
digital7 = 'OFF'
if digital8 == 1:
digital8 = 'ON'
else:
digital8 = 'OFF'
sensor1_level = ReadChannel(sensor1_channel)
sensor1_volts = ConvertVolts(sensor1_level,2)
sensor2_level = ReadChannel(sensor2_channel)
sensor2_volts = ConvertVolts(sensor2_level,2)
sensor3_level = ReadChannel(sensor3_channel)
sensor3_volts = ConvertVolts(sensor3_level,2)
sensor4_level = ReadChannel(sensor4_channel)
sensor4_volts = ConvertVolts(sensor4_level,2)
sensor5_level = ReadChannel(sensor5_channel)
sensor5_volts = ConvertVolts(sensor5_level,2)
sensor6_level = ReadChannel(sensor6_channel)
sensor6_volts = ConvertVolts(sensor6_level,2)
sensor7_level = ReadChannel(sensor7_channel)
sensor7_volts = ConvertVolts(sensor7_level,2)
sensor8_level = ReadChannel(sensor8_channel)
sensor8_volts = ConvertVolts(sensor8_level,2)
if fdtime >= fstore:
foldtime = fnewtime
googlepage = "https://script.google.com/macros/s/"
mygooglekey = "AKfycag8ıtng1231byDLLxRSLBLLqdadekqtjr_0wSgFJKfqRassd526s21QtLeO9oJMhUqzFBs"
wtime = time.strftime("%d/%m/%Y %H:%M:%S")
content = urllib.urlopen("%s%s/exec?DATE=%s&Sensor1=%s&Sensor2=%s&Sensor3=%s&Sensor4=%s&Sensor5=%s&Sensor6=%s&Sensor7=%s&Sensor8=%s&Digital1=%s&Digital2=%s&Digital3=%s&Digital4=%s&Digital5=%s&Digital6=%s&Digital7=%s&Digital8=%s" %(googlepage, mygooglekey, wtime, sensor1_volts, sensor2_volts, sensor3_volts, sensor4_volts, sensor5_volts, sensor6_volts, sensor7_volts, sensor8_volts, digital1, digital2, digital3, digital4, digital5, digital6, digital7, digital8)).read()
print "-----------------------------------------------------------------------------"
print(" Sensor-1 Sensor-2 Sensor-3 Sensor-4 Sensor-5 Sensor-6 Sensor-7 Sensor-8")
print(" {} - ({}V) {} - ({}V) {} - ({}V) {} - ({}V) {} - ({}V) {} - ({}V) {} - ({}V) {} - ({}V)".format(sensor1_level,sensor1_volts,sensor2_level,sensor2_volts,sensor3_level,sensor3_volts,sensor4_level,sensor4_volts,sensor5_level,sensor5_volts,sensor6_level,sensor6_volts,sensor7_level,sensor7_volts,sensor8_level,sensor8_volts))
print(" Digital-1 Digital-2 Digital-3 Digital-4 Digital-5 Digital-6 Digital-7 Digital-8")
print(" {} {} {} {} {} {} {} {} ".format(digital1,digital2,digital3,digital4,digital5,digital6,digital7,digital8))
time.sleep(delay)
