Really sorry about the lack of code tags. I have them turned on in my account settings, but they're off for this post, and I can't see a button to change that. I saw a note in the forum documentation saying an administrator has to enable this. If there's a way for me to turn them on, let me know and I'll fix it.
I hope my subject was descriptive enough. I am getting an error when calling a method in a class I made. The method has been defined as read_temp(self):
but it still seems to think it should not take any arguments.
My source code is this:
Code: Select all
import time
import math
import pyb
from pyb import UART
class tempSensor():
"""Thermistor object takes IO pins for power and signal and
nominal resistance of parallel resistor. Methods allow for reading
the temperature. Main 'public' method will return float."""
def __init__(self, sensor_pin, power_pin, resistance):
"""Pin args are strings corresponding to pyb names, resistance is int"""
self.sensor_pin = pyb.ADC(sensor_pin)
self.power_pin = pyb.Pin(power_pin, pyb.Pin.OUT_PP)
self.resistance = resistance
self.thermistor_nominal = 10000
self.temperature_nominal = 25
self.bcoefficient = 3950
self.numsamples = 5
def _read_sensor(self):
"""'Private' method to set power pin up and read value from thermistor.
Power is only on temporarily to avoid heating up thermistor."""
self.power_pin.high()
time.sleep(1)
average = 0
for i in range(self.numsamples):
average += self.sensor_pin.read()
self.power_pin.low()
return average / self.numsamples
def read_temp(self):
"""'Public' method to allow user to get temperature value from sensor."""
reading = self._read_sensor()
reading = 4095 / reading - 1
reading = resistance / reading
temp = reading / self.thermistor_nominal
temp = math.log(temp)
temp /= self.bcoefficient
temp += 1.0 / (self.temperature_nominal + 273.15)
temp = 1.0 / temp
temp -= 273.15
round(temp, 1) # Accuracy will be lost beyond one floating point
return temp
def esp_transmit(uart, reading):
uart.write("AT+CIPSEND={}\r\n".format(len(reading)))
time.sleep(5)
uart.write(str(reading))
def sensor_test():
uart = UART(4, 115200)
uart.init(115200, bits=8, parity=None, stop=1)
uart.write('AT+CIPSTART="UDP","192.168.0.19",6789\r\n')
time.sleep(5)
sensor_left_power = 'Y3'
sensor_left_read = 'Y12'
sensor_right_power = 'Y1'
sensor_right_read = 'Y11'
resistance = 10000
sensor_left = tempSensor(sensor_left_read, sensor_left_power, resistance)
sensor_right = tempSensor(sensor_right_read, sensor_right_power, resistance)
while True:
esp_transmit(uart, sensor_left.read_temp())
time.sleep(5)
esp_transmit(uart, str(sensor_right.read_temp()))
time.sleep(5)
sensor_test()
In the REPL, when I import this source file, and create a sensor object, as soon as I call read_temp(), I get
TypeError: read_temp() takes 0 positional arguments but 1 were given
The same goes if I call _read_sensor() directly.
This error normally occurs if self has not been used as a parameter when defining the method. That is the only case I have seen online.
I did also see that MicroPython has a problem with handling arguments sometimes: https://docs.micropython.org/en/latest/ ... #functions
It made me think that there could be some issue with how micropython is handling my code.
When I define all this code in the REPL myself, however, it works without a problem. I even got it to return some values from reading the sensors. So somehow it has an issue with this module.
By the way, I'm using a pyboard, V1.1. tempobjects.py, the name of this module, is in the main directory for the board. boot.py contains the instruction, pyb.main('tempobjects.py')
I'm all out of ideas. Is there something I'm missing about the way MicroPython handles classes?
Thanks for your help.
Edit by admin: Enabled code tags
