class Car(object):
def __init__(self, is_debug=False):
'''
Car构造器函数
'''
# 电池ADC采样
self.battery_adc = BatteryVoltage(gpio_dict['BATTERY_ADC'],
is_debug=False)
# 用户按键
self.user_button = Button(0,
callback=lambda pin: self.stop_trigger(pin))
try:
# 创建一个I2C对象
i2c = I2C(scl=Pin(gpio_dict['I2C_SCL']),
sda=Pin(gpio_dict['I2C_SDA']),
freq=car_property['I2C_FREQUENCY'])
# 创建舵机云台对象
self.cloud_platform = CloudPlatform(i2c)
except:
print('[ERROR]: pca9885舵机驱动模块初始化失败')
print('[Hint]: 请检查接线')
self.speed_percent = 70 # 小车默认速度
# 左侧电机
self.left_motor = Motor(0)
self.left_motor.stop() # 左侧电机停止
# 右侧电机
self.right_motor = Motor(1)
self.right_motor.stop() # 右侧电机停止
# 小车停止标志位
self.stop_flag = False
self.is_debug = is_debug # 是否开始调试模式
def stop(self):
'''停车'''
self.left_motor.speed_percent = 0
self.right_motor.speed_percent = 0
def stop_trigger(self, pin):
'''
切换小车的停止位
'''
self.stop_flag = not self.stop_flag
if self.stop_flag:
self.stop()
if self.is_debug:
print('切换stopflag flag={}'.format(self.stop_flag))
def go_forward(self, speed_percent=None, delay_ms=None):
'''
小车前进
'''
if speed_percent is None:
speed_percent = self.speed_percent
else:
speed_percent = float(speed_percent)
if delay_ms is not None:
delay_ms = int(delay_ms)
self.left_motor.speed_percent = speed_percent
self.right_motor.speed_percent = speed_percent
if delay_ms is not None:
delay_ms = int(float(delay_ms))
utime.sleep_ms(delay_ms)
self.stop()
def go_backward(self, speed_percent=None, delay_ms=None):
'''
小车后退
'''
if speed_percent is None:
speed_percent = self.speed_percent
else:
speed_percent = float(speed_percent)
if delay_ms is not None:
delay_ms = int(delay_ms)
self.left_motor.speed_percent = -1 * speed_percent
self.right_motor.speed_percent = -1 * speed_percent
if delay_ms is not None:
delay_ms = int(float(delay_ms))
utime.sleep_ms(delay_ms)
self.stop()
def turn_left(self, speed_percent=None, delay_ms=None):
'''
小车左转
'''
if speed_percent is None:
speed_percent = self.speed_percent
else:
speed_percent = float(speed_percent)
self.left_motor.speed_percent = -1 * speed_percent
self.right_motor.speed_percent = speed_percent
if delay_ms is not None:
delay_ms = int(float(delay_ms))
utime.sleep_ms(delay_ms)
self.stop()
def turn_right(self, speed_percent=None, delay_ms=None):
'''
小车右转
'''
if speed_percent is None:
speed_percent = self.speed_percent
else:
speed_percent = float(speed_percent)
self.left_motor.speed_percent = speed_percent
self.right_motor.speed_percent = -1 * speed_percent
if delay_ms is not None:
delay_ms = int(float(delay_ms))
utime.sleep_ms(delay_ms)
self.stop()
def move(self, left_speed_percent, right_speed_percent, delay_ms=None):
left_speed_percent = float(left_speed_percent)
right_speed_percent = float(right_speed_percent)
self.left_motor.speed_percent = left_speed_percent
self.right_motor.speed_percent = right_speed_percent
if delay_ms is not None:
delay_ms = int(float(delay_ms))
utime.sleep_ms(delay_ms)
self.stop()
def deinit(self):
'''
释放资源
'''
self.battery_adc.deinit()
self.user_button.deinit()
self.left_motor.deinit()
self.right_motor.deinit()
def log(self):
# 打印日志 TODO
print('[INFO] battery voltage: {}'.format(
self.battery_adc.battery_voltage))
print('[INFO] default velocity (percent): {}'.format(
self.speed_percent))
class ShadeController(BaseThing):
def __init__(self):
import machine
if getattr(machine, "reset_cause", None) != None:
reset_names = [
'0', 'PWRON', 'HARD', 'Watchdog', 'DEEPSLEEP', 'SOFT'
]
cause = machine.reset_cause()
if cause < machine.PWRON_RESET or cause > machine.SOFT_RESET:
logger.warning("Unknown reset cause: %d", cause)
else:
logger.debug("Reset cause: %s", reset_names[cause])
self.rtc = machine.RTC()
super().__init__()
# if a parameter is not restored from persistence, then add it with a default value
if 'position' not in self._current_state['params']:
self._current_state['params']['position'] = "unknown"
self._operations['position'] = self._position
# add tests to dictionary of available test operations
self._test_operations['current'] = self._test_current_sensor
self._test_operations['motor'] = self._test_motor
self._test_operations['motor2'] = self._test_motor2
self._test_operations['set-position'] = self._set_position
self._conditions['temperature'] = {
'get': self.get_temperature,
'threshold': 2
} # report on 2 degree changes
# report batteryVoltage on changes of 200 mV or 20 minutes
self._conditions['batteryVoltage'] = {
'get': self.get_battery_voltage,
'threshold': 200,
'interval': 1200
}
self._start_ticks = None
PCB_version = 3
if PCB_version == 0:
# the following are the GPIO numbers
self.PIN_LED = 2
self.PIN_POWER_ENABLE = 14 # D5 on the nodeMCU board
# self.PIN_MOTOR_ENABLE1 = 12 #D6
# self.PIN_MOTOR_ENABLE2 = 13 #D7
self.PIN_MOTOR_ENABLE1 = 15 #D8
self.PIN_MOTOR_ENABLE2 = 2 #D4
# self.PIN_MOTOR_EN1 = [12, 15]
# self.PIN_MOTOR_EN2 = [13, 2]
self.PIN_CHARGING_DISABLE = 0 #D3
self.PIN_WAKEUP = 16 #D0
self.PIN_SCL = 5 #D1
self.PIN_SDA = 4 #D2
elif PCB_version == 3:
self.PIN_LED = 16
self.PIN_POWER_ENABLE = 16
self.PIN_MOTOR1_ENABLES = (5, 17)
self.PIN_MOTOR2_ENABLES = (18, 19)
self.PIN_CHARGING_DISABLE = 21
self.PIN_SCL = 22
self.PIN_SDA = 23
self.LM75B_ADDR = 0x4F # 79 decimal
self.ATECC508_ADDR = 0x60 # 96 decimal
else:
import sys
logger.error("Unknown PCB_rev: %d", PCB_rev)
sys.exit(1)
self.I2C_FREQ = 100000
# self.INA219_ADDR = 0x40 #64 on the adafruit module
self.INA219_ADDR = 0x45 #69 decimal
self.ppin_led = None
self.ppin_power_enable = machine.Pin(self.PIN_POWER_ENABLE,
machine.Pin.OUT,
value=0)
self.ppin_charging_disable = machine.Pin(self.PIN_CHARGING_DISABLE,
machine.Pin.OUT,
value=1)
self.i2c = machine.I2C(scl=machine.Pin(self.PIN_SCL),
sda=machine.Pin(self.PIN_SDA),
freq=self.I2C_FREQ)
# the following is commented out to save power
# i2c_devices = None
# try:
# i2c_devices = self.i2c.scan()
# except:
# print("Exception i2c bus scan")
# if (len(i2c_devices) < 1):
# print("No i2c devices detected")
self.current_sensor = None
# the following are shade direction constants that make it easier to understand motor direction
self.LOWER = 0
self.RAISE = 1
self.MOTOR_START_SPEED = 30 # speed is in percentage
self.MOTOR_SPEED_RAMP = 5 # increments to speed up the motor, in percentage
self.MOTOR_SENSOR_SAMPLE_INTERVAL = 10 # 10 milliSeconds between current samples when the motor is on
self.MOTOR_AVERAGING_SAMPLES = 4 # the current is sampled this many times because it may be noisy due to the motor
import array
# pre-allocate current sample arrays - used by the position routine to threshold motor currents
self.STARTING_CURRENT_SAMPLE_COUNT = 16
self.starting_currents = array.array(
'i', (0 for _ in range(self.STARTING_CURRENT_SAMPLE_COUNT)))
self.starting_current_next = 0
self.STOPPING_CURRENT_SAMPLE_COUNT = 16
self.stopping_currents = array.array(
'i', (0 for _ in range(self.STOPPING_CURRENT_SAMPLE_COUNT)))
self.stopping_current_next = 0
#the following are used by _activate_motor to detect current threshold crossing
self.averaging_sum = 0
self.average_current_threshold = 0
def connect(self):
""" activates the wlan and polls to see if connected
returns a tuple:
- a boolean to indicate successful connection or not
- a msg to display if connection failed
"""
import esp, network
from sys import platform
from utime import sleep_ms
from setwifi import setwifi as setwifi
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
if platform == 'esp32':
cfg_info = self._get_cfg_info("wifi_info.txt")
# cfg_info = {"SSID": "xx", "password": "******"}
if not cfg_info:
setwifi()
# setwifi should write the wifi_info file, so read it
cfg_info = self._get_cfg_info("wifi_info.txt")
if not cfg_info:
return False, "Error: could not obtain wifi configuration"
wlan.connect(cfg_info['SSID'], cfg_info['password'])
connected = False
for _ in range(180):
connected = wlan.isconnected()
if connected:
return True, None
else:
sleep_ms(33)
if not connected:
setwifi()
return False, "Warning: unable to connect to WiFi; setWiFi run to get new credentials"
@property
def id(self):
from machine import unique_id
id_reversed = unique_id()
id_binary = [
id_reversed[n] for n in range(len(id_reversed) - 1, -1, -1)
]
return "ESP-" + "".join("{:02x}".format(x) for x in id_binary)
def time(self):
from ntptime import time as get_ntp_time
import utime
# The shadow timestamp is from 1970-01-01 vs micropython is from 2000-01-01
SECONDS_BETWEEN_1970_2000 = 946684800
time_tuple = None
last_exception = None
if self._start_ticks is None:
for i in range(11):
utime.sleep_ms(333)
try:
self._timestamp = get_ntp_time()
break
except Exception as e:
last_exception = str(e)
logger.debug("Exception in get NTP: %s", last_exception)
# the 1st NTP request after a hard reset and then an IP connect always fails, so retry quickly
if i < 2:
utime.sleep_ms(33)
else:
utime.sleep_ms(666)
if self._timestamp is None:
logger.error(
"Failed to get time from NTP after %d attempts; Last exception was '%s'.",
i + 1, last_exception)
elif type(self._timestamp).__name__ == 'int':
logger.debug("Recieved NTP timestamp after %d attempts", i + 1)
try:
time_tuple = utime.localtime(self._timestamp)
# adjust the stored timestamp used for reporting conditions based on an interval
self._start_ticks = utime.ticks_ms()
self._timestamp += SECONDS_BETWEEN_1970_2000
except Exception as e:
logger.error(
"Exception '%s' on timestamp conversion; timestamp: %d",
str(e), self._timestamp)
else:
logger.error("NTP timestamp not an int: %s", self._timestamp)
else:
# get updated time by adding elapsed time to existing timestamp
# - shift right 10 is approx equal to divide by 1000 in order to get seconds
elapsed_secs = utime.ticks_diff(utime.ticks_ms(),
self._start_ticks) >> 10
time_tuple = utime.localtime(self._timestamp -
SECONDS_BETWEEN_1970_2000 +
elapsed_secs)
return time_tuple
def sleep(self, msg=None):
import machine
from sys import platform
from utime import sleep_ms
try:
import webrepl
except:
webrepl = None
LOG_FILENAME = "./log.txt"
if msg is not None:
logger.warning(msg)
with open(LOG_FILENAME, 'a') as log_file:
log_file.write(msg + "\n")
if self.current_sensor is not None:
self.current_sensor.stop()
if self._current_state['params']['sleep'] < 1:
# exit: stop the infinite loop of main & deep-sleep
from sys import exit
logger.info("Staying awake due to sleep parameter < 1.")
if webrepl is not None:
webrepl.start()
# configure timer to issue reset, so the device will reboot and fetch a new shadow state
TIME_BEFORE_RESET = 120000 # 3 minutes in milliseconds
tim = machine.Timer(-1)
# tim.init throws an OSError 261 after a soft reset; this is a work-around:
try:
tim.init(period=TIME_BEFORE_RESET,
mode=machine.Timer.ONE_SHOT,
callback=lambda t: machine.reset())
except Exception as e:
logger.warning(
"Exception '%s' on tim.init; No reset after a timer expiry.",
e)
exit(0)
if webrepl is not None:
webrepl.stop()
logger.info("Going to sleep for %s seconds.",
self._current_state['params']['sleep'])
if platform == 'esp32':
# multiply sleep time by approx 1000 (left shift by 10)
machine.deepsleep(self._current_state['params']['sleep'] << 10)
else:
self.rtc.irq(trigger=self.rtc.ALARM0, wake=machine.DEEPSLEEP)
self.rtc.alarm(self.rtc.ALARM0,
self._current_state['params']['sleep'] << 10)
machine.deepsleep()
def _reported_state_get(self):
# add current arrays as strings to report
if self.starting_currents[0] != 0:
report_conditions_time_based = True #update conditions report after operating the motor
currents = ""
for i in self.starting_currents:
currents = currents + str(i) + " "
# remove trailing space
self._reported_state['starting_currents'] = currents[:-1]
# stopping currents start at next and loop around
currents = ""
idx = self.stopping_current_next
for _ in range(self.STOPPING_CURRENT_SAMPLE_COUNT):
currents = currents + str(self.stopping_currents[idx]) + " "
idx = idx + 1
if idx > (self.STOPPING_CURRENT_SAMPLE_COUNT - 1):
idx = 0
self._reported_state['stopping_currents'] = currents[:-1]
return super()._reported_state_get()
reported_state = property(_reported_state_get)
def _shadow_state_get(self):
return super()._shadow_state_get()
def _shadow_state_set(self, shadow_state):
if self._has_history and self._restored_state['history'][0][
'done'] != 1:
# The operation didn't finished, so update the status to be reflected in an updated report
failed_operation = self._restored_state['history'][0]['op']
self._current_state['params'][failed_operation] = "unknown"
super()._shadow_state_set(shadow_state)
shadow_state = property(_shadow_state_get, _shadow_state_set)
def blink_led(self, t=50):
import machine
from utime import sleep_ms
if self.ppin_led is None:
self.ppin_led = machine.Pin(self.PIN_LED, machine.Pin.OUT, value=0)
else:
self.ppin_led.init(machine.Pin.OUT)
sleep_ms(t)
# leave the pin as an input to not mess up any pin state in reset requirements
self.ppin_led.init(machine.Pin.IN)
def _persist_state(self):
""" the ESP can use RTC memory for a persistent store instead of the flash filesystem"""
import ujson
self.rtc.memory(ujson.dumps(self._current_state))
def _restore_state(self):
import ujson
try:
tmp = ujson.loads(self.rtc.memory())
logger.debug("restored state: %s", tmp)
if type(tmp) is not dict or 'params' not in tmp:
logger.warning(
"_restore_state: RTC memory did not have parameters")
tmp = {}
except:
logger.warning("_restore_state: RTC memory was not JSON")
tmp = {}
return tmp
def _position(self):
""" validates shadow state variables: position, duration, reverse -- and then calls _activate_motor
Inputs: shadow_state
Returns: status string
"""
status = self._instance_current_sensor()
if status is not None:
return "Fail (position): " + status
MAX_DURATION = 59
POSITIONS = ['open', 'closed', 'half']
class Positions:
OPEN = 0
CLOSED = 1
HALF = 2
if self._shadow_state['state']['desired']['position'] not in POSITIONS:
return "Error: unrecognized position: {0}".format(
self._shadow_state['state']['desired']['position'])
if self._shadow_state['state']['desired']['duration'] > MAX_DURATION:
return "Error: duration: {0} is longer than max value: {1}".format(
self._shadow_state['state']['desired']['duration'],
MAX_DURATION)
if self._shadow_state['state']['desired']['duration'] < 1:
return "Error: duration: {0} is zero or negative".format(
self._shadow_state['state']['desired']['duration'])
# if POST fails, then AWS-IOT state could mismatch persisted/real state
if self._current_state['params']['position'] == self._shadow_state[
'state']['desired']['position']:
return "Already in position: " + self._shadow_state['state'][
'desired']['position']
duration = self._shadow_state['state']['desired'][
'duration'] * 1000 #convert to millisecond
direction = self.LOWER
if self._shadow_state['state']['desired']['position'] == POSITIONS[
Positions.OPEN]:
direction = self.RAISE
# halve the duration if currently in the half position or going to the half position
if self._shadow_state['state']['desired']['position'] == POSITIONS[
Positions.HALF]:
duration = duration >> 1
if self._current_state['params']['position'] == POSITIONS[
Positions.CLOSED]:
direction = self.RAISE
# if the current position is unknown, the direction will be to lower, and the current position will stay unknown.
if self._current_state['params']['position'] == POSITIONS[
Positions.HALF]:
duration = duration >> 1
# invert direction if shade is of type 'top_down', as indicated by bit 1: 0x0010
if (self._shadow_state['state']['desired']['reverse'] & 2) != 0:
direction = direction ^ 1
# dont move much when lowering if position is unknown since the current sensor can't be used to figure the stopping position
if self._current_state['params'][
'position'] not in POSITIONS and direction == self.LOWER:
duration = 200
# it takes longer to go the same distance when raising, so increase the duration by ??30%
if direction == self.RAISE:
duration = duration + (duration >> 2) # + (duration >> 4)
measured_duration = self._activate_motor(duration, direction,
self.PIN_MOTOR1_ENABLES)
if measured_duration > 1:
if direction == self.RAISE or measured_duration >= duration:
self._current_state['params']['position'] = self._shadow_state[
'state']['desired']['position']
else:
self._current_state['params']['position'] = 'unknown'
status = "Done: new position: {0}; motor on for: {1} msec".format(
self._current_state['params']['position'], measured_duration)
if self.averaging_sum > self.average_current_threshold:
status = status + "; Current: {0} over Threshold: {1}".format(
self.averaging_sum, self.average_current_threshold)
else:
status = "Error on position; I2C error: {0}".format(
measured_duration)
return status
def _set_position(self):
""" Used to set the persisted 'position' to the current desired position.
Normally used to transition out of the position==unknown state
"""
self._current_state['params']['position'] = self._shadow_state[
'state']['desired']['position']
return "position set to: " + self._current_state['params']['position']
def _test_current_sensor(self):
status = self._instance_current_sensor()
if self.current_sensor is None:
status = "Fail (current test): " + status
else:
self.current_sensor.start()
mAmps = self.current_sensor.get_current_ma()
mVolts = self.current_sensor.get_bus_mv()
status = "Pass: Current: {0:d} BusVolts: {1:d}".format(
mAmps, mVolts)
return status
def _test_motor(self):
return self._test_motor_base(self.PIN_MOTOR1_ENABLES)
def _test_motor2(self):
return self._test_motor_base(self.PIN_MOTOR2_ENABLES)
def _test_motor_base(self, pins):
""" Operates the motor for the number of milliseconds specified in test_param
A negative test_param operates the motor in the reverse direction
"""
if not self._has_history:
status = "Skipping first motor test after initialization"
else:
status = self._instance_current_sensor()
if status is not None:
status = "Fail (motor test): " + status
else:
duration = self._shadow_state['state']['desired']['test_param']
if duration < 0:
direction = self.LOWER
else:
direction = self.RAISE
duration = abs(duration)
if duration < 55000:
measured_duration = self._activate_motor(
duration, direction, pins)
if measured_duration >= duration:
status = "Pass: motor on for " + str(
measured_duration) + " msec."
else:
status = "Fail: motor on for " + str(
measured_duration) + " msec."
else:
status = "Fail: test_param too large for motor test: " + str(
duration)
return status
def _instance_current_sensor(self):
from ina219 import INA219
status = None
if self.current_sensor is None:
if self.i2c is None:
status = "I2C not initialized when creating current sensor"
else:
try:
self.current_sensor = INA219(i2c=self.i2c,
i2c_addr=self.INA219_ADDR)
if not self.current_sensor.in_standby_when_initialized:
logger.warning("Current sensor not in standby.")
except:
status = "I2C access to current sensor failed"
return status
def _activate_motor(self, duration, direction, pins):
"""Instantiates a motor and turns on the motor driver for the duration (expressed in milliseconds)
self.current_sensor should have been instantiated before calling
"""
from motor import Motor
import machine, utime
elapsed_time = 0
self.average_current_threshold = self._shadow_state['state'][
'desired']['threshold'] * self.MOTOR_AVERAGING_SAMPLES
#invert direction if reverse bit is set
motor_direction = direction ^ (
self._shadow_state['state']['desired']['reverse'] & 1)
# self.motor = Motor(self.PIN_MOTOR_ENABLE1, self.PIN_MOTOR_ENABLE2)
self.motor = Motor(pins)
#enable 12V and disable charging
if self.ppin_power_enable is None:
self.ppin_power_enable = machine.Pin(self.PIN_POWER_ENABLE,
machine.Pin.OUT,
value=1)
else:
self.ppin_power_enable.value(1)
if self.ppin_charging_disable is None:
self.ppin_charging_disable = machine.Pin(self.PIN_CHARGING_DISABLE,
machine.Pin.OUT,
value=0)
else:
self.ppin_charging_disable.value(0)
utime.sleep_ms(50) # wait for power to stabilize
self.current_sensor.start()
start_ticks = utime.ticks_ms()
self.motor.start(direction=motor_direction,
speed=self.MOTOR_START_SPEED)
while elapsed_time < duration:
sample_ticks_begin = utime.ticks_ms()
current_sample = self._update_current_arrays()
# !! TODO: stop calling adjustSpeed after calling it N times
if (current_sample <
self._shadow_state['state']['desired']['threshold']):
self.motor.adjust_speed(self.MOTOR_SPEED_RAMP)
# check the avg of the last N samples don't exceed the threshold
self.averaging_sum = 0
for averaging_offset in range(-self.MOTOR_AVERAGING_SAMPLES, 0):
averaging_index = self.stopping_current_next + averaging_offset
if (averaging_index < 0):
averaging_index += self.STOPPING_CURRENT_SAMPLE_COUNT
self.averaging_sum += self.stopping_currents[averaging_index]
# print("Index: {0} -- Value: {1} -- Sum: {2}".format(averaging_index, self.stopping_currents[averaging_index], self.averaging_sum))
# stop the motor if over the threshold
if self.averaging_sum > self.average_current_threshold:
break
delay_time = self.MOTOR_SENSOR_SAMPLE_INTERVAL - (
utime.ticks_ms() - sample_ticks_begin)
utime.sleep_ms(delay_time)
elapsed_time = utime.ticks_ms() - start_ticks
self.motor.stop()
self.ppin_power_enable.value(0)
self.ppin_charging_disable.value(1)
# re-init pins so they are tri-state
self.ppin_power_enable.init(machine.Pin.IN)
self.ppin_charging_disable.init(machine.Pin.IN)
self.motor.deinit()
del self.motor
return elapsed_time
def _update_current_arrays(self):
import utime
#assumes caller has already instanced & checked & started the sensor
current_sample = self.current_sensor.get_current_ma()
for samples in range(3):
utime.sleep_ms(5)
current_sample += self.current_sensor.get_current_ma()
current_sample = current_sample >> 2 #take average of 4 samples
if (self.starting_current_next < self.STARTING_CURRENT_SAMPLE_COUNT):
self.starting_currents[self.starting_current_next] = current_sample
self.starting_current_next += 1
# continuously update stopping array; when at end, loop back to the beginning
self.stopping_currents[self.stopping_current_next] = current_sample
self.stopping_current_next += 1
if (self.stopping_current_next >
self.STOPPING_CURRENT_SAMPLE_COUNT - 1):
self.stopping_current_next = 0
return current_sample
def get_battery_voltage(self):
mVolts = -1
status = self._instance_current_sensor()
if status is None:
self.current_sensor.start()
mVolts = self.current_sensor.get_bus_mv()
return mVolts
def get_temperature(self):
from utime import sleep_ms
cfg = self.i2c.readfrom(self.LM75B_ADDR, 1)
if not (cfg[0] & 0x01):
logger.warning("Temperature sensor not shutdown.")
self.i2c.writeto_mem(
self.LM75B_ADDR, 1,
b'\x00') # write cfg register to take out of shutdown state
sleep_ms(105) # wait for a conversion period
value = bytearray(2)
self.i2c.readfrom_mem_into(self.LM75B_ADDR, 0, value)
rounding = (value[1] &
0x80) >> 7 #if between 0.5 and 0.875 then round up or down
if (value[0] & 0x80):
# negative temp
t = value[0] - 0x100 - rounding
else:
t = value[0] + rounding
self.i2c.writeto_mem(
self.LM75B_ADDR, 1,
b'\x01') # write cfg register to put into shutdown state
return t
def get_pwr_in_voltage(self):
from machine import ADC, Pin
adc_35 = ADC(Pin(35))
adc_35.atten(ADC.ATTN_11DB)
DIVIDER_COEFF = 2.1 # why is this 2.1 instead of 2 ?
return DIVIDER_COEFF * adc_35.read() * 3.3 / 4096