ble_temperature

# This example demonstrates a simple temperature sensor peripheral
#
# The sensor's local value is updated, and it will notify
# any connected central every 10 seconds.
from helper import GetTemperature, connect_to_wifi, WifiServer, to_json
import bluetooth
import random
import struct
import time
import machine
import ubinascii
from ble_advertising import advertising_payload
from micropython import const
from machine import Pin

from helper import GetTemperature, connect_to_wifi, WifiServer, to_json
import network
import usocket
from time import time, sleep
import network
import time
from umqtt.simple import MQTTClient
import machine
from picozero import pico_temp_sensor
from machine import Pin
import micropython
import ustruct as struct
import json
import time
import random

adcpin = 4
sensor = machine.ADC(adcpin)


name = "PW_1"
_IRQ_CENTRAL_CONNECT = const(1)
_IRQ_CENTRAL_DISCONNECT = const(2)
_IRQ_GATTS_INDICATE_DONE = const(20)

_FLAG_READ = const(0x0002)
_FLAG_NOTIFY = const(0x0010)
_FLAG_INDICATE = const(0x0020)

# org.bluetooth.service.environmental_sensing
_ENV_SENSE_UUID = bluetooth.UUID(0x181A)
# org.bluetooth.characteristic.temperature
_TEMP_CHAR = (
bluetooth.UUID(0x2A6E),
_FLAG_READ | _FLAG_NOTIFY | _FLAG_INDICATE,
)
_ENV_SENSE_SERVICE = (
    _ENV_SENSE_UUID,
(_TEMP_CHAR,),
)

# org.bluetooth.characteristic.gap.appearance.xml
_ADV_APPEARANCE_GENERIC_THERMOMETER = const(768)

class BLETemperature:
    def __init__(self, ble, name="PW_1"):
        self._sensor_temp = GetTemperature()
        self._ble = ble
        self._ble.active(True)
        self._ble.irq(self._irq)
        ((self._handle,),) = self._ble.gatts_register_services((_ENV_SENSE_SERVICE,))
        self._connections = set()
        if len(name) == 0:
            name = 'Pico %s' % ubinascii.hexlify(self._ble.config('mac')[1],':').decode().upper()
            print('Sensor name %s' % name)
            self._payload = advertising_payload(name=name, services=[_ENV_SENSE_UUID])
            self._advertise()

    def _irq(self, event, data):
    # Track connections so we can send notifications.
        if event == _IRQ_CENTRAL_CONNECT:
            conn_handle, _, _ = data
            self._connections.add(conn_handle)
        elif event == _IRQ_CENTRAL_DISCONNECT:
            conn_handle, _, _ = data
            self._connections.remove(conn_handle)
        # Start advertising again to allow a new connection.
            self._advertise()
        elif event == _IRQ_GATTS_INDICATE_DONE:
            conn_handle, value_handle, status = data

    def update_temperature(self, notify=False, indicate=False):
    # Write the local value, ready for a central to read.
        temp_deg_c = self._get_temp()
        print("write temp %.2f degc" % temp_deg_c);
        self._ble.gatts_write(self._handle, struct.pack("<h", int(temp_deg_c * 100)))
        if notify or indicate:
            for conn_handle in self._connections:
                if notify:
                    self._ble.gatts_notify(conn_handle, self._handle)
                if indicate:
        # Indicate connected centrals.
                    self._ble.gatts_indicate(conn_handle, self._handle)

    def _advertise(self, interval_us=500000):
        self._ble.gap_advertise(interval_us, adv_data=self._payload)

    def _get_temp(self):
        adc_value = sensor.read_u16()
        volt = (3.3/65535) * adc_value
        temperature = 27 - (volt - 0.706)/0.001721
        temp = str(round(temperature, 1))
#    timestamp = datetime.now().isoformat()
        print(temp)
        return temperature



# ref https://github.com/raspberrypi/pico-micropython-examples/blob/master/adc/temperature.py
"""
    def _get_temp(self):
        conversion_factor = 3.3 / (65535)
        reading = self._sensor_temp.read_u16() * conversion_factor
        temperature = 27 - (volt - 0.706)/0.001721

# The temperature sensor measures the Vbe voltage of a biased bipolar diode, connected to the fifth ADC channel
# Typically, Vbe = 0.706V at 27 degrees C, with a slope of -1.721mV (0.001721) per degree.

        return temperature
"""    


ble = bluetooth.BLE()
temp = BLETemperature(ble)
counter = 0
led = Pin('LED', Pin.OUT)
while True:
    if counter % 10 == 0:
        temp.update_temperature(notify=True, indicate=False)
        led.toggle()
        time.sleep_ms(1000)
        counter += 1