initial commit

Author: g-sam

.gitignore

@@ -0,0 +1,2 @@
+webrepl
+data.txt

boot.py

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+# This file is executed on every boot (including wake-boot from deepsleep)
+#import esp
+#esp.osdebug(None)
+import gc
+import webrepl
+gc.collect()
+
+print('\nbooting...')
+
+def do_connect():
+    import network
+
+    file = open('data.txt')
+    pw = file.read().strip()
+    file.close()
+
+    ap_if = network.WLAN(network.AP_IF)
+    ap_if.config(essid='Polly', password=pw)
+    print('access point Polly open')
+
+    sta_if = network.WLAN(network.STA_IF)
+    if not sta_if.isconnected():
+        print('connecting to network...')
+        sta_if.active(True)
+        sta_if.connect('Bam-net', pw)
+        while not sta_if.isconnected():
+            pass
+    print('connected at:', sta_if.ifconfig())
+
+
+do_connect()
+
+webrepl.start()

main.py

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+import sds011
+import machine
+import time
+import esp
+
+if machine.reset_cause() == machine.DEEPSLEEP_RESET:
+    print('Woke from a deep sleep')
+
+READ_SECONDS = 55
+SLEEP_SECONDS = 5
+
+sds011.wake()
+sds011.read(READ_SECONDS * 1000);
+sds011.sleep();
+# esp.deepsleep(SLEEP_SECONDS * 1000000)

mqtt.py

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+from umqtt.robust import MQTTClient
+import ubinascii as binascii
+import machine
+import ujson as json
+
+MQTT_CONFIG = { 'broker': '192.168.0.3',
+               'client_id': b'polly_' + binascii.hexlify(machine.unique_id()) }
+
+MQTT_CONFIG.update({'topic': b'polly/' + MQTT_CONFIG['client_id']})
+
+client = MQTTClient(MQTT_CONFIG['client_id'], MQTT_CONFIG['broker'])
+client.connect()
+
+print('MQTT client connected to broker', MQTT_CONFIG['broker'])
+
+def publish(msg):
+    global client
+    msg.update({
+        'client_id': MQTT_CONFIG['client_id']
+    })
+    client.publish(MQTT_CONFIG['topic'], bytes(json.dumps(msg), 'utf8'))
+    print('Message sent to', MQTT_CONFIG['broker'], 'on', MQTT_CONFIG['topic'])

sds011.py

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+"""
+Reply format. See http://cl.ly/ekot
+
+0 Header   '\xaa'
+1 Command  '\xc0'
+2 DATA1    PM2.5 Low byte
+3 DATA2    PM2.5 High byte
+4 DATA3    PM10 Low byte
+5 DATA4    PM10 High byte
+6 DATA5    ID byte 1
+7 DATA6    ID byte 2
+8 Checksum Low byte of sum of DATA bytes
+9 Tail     '\xab'
+
+"""
+
+import machine
+import ustruct as struct
+import mqtt
+import sys
+import utime as time
+
+uart = machine.UART(0, 9600)
+uart.init(9600, bits=8, parity=None, stop=1)
+
+def wake():
+    global uart
+    while uart.read(1) == None:
+        print('Sending wake command to sds011')
+        cmd = b'\xaa\xb4\x06\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\x06\xab'
+        uart.write(cmd)
+    print('sds011 woke up!')
+
+def sleep():
+    global uart
+    AWAKE = True
+    while AWAKE:
+        print('Sending sleep command to sds011')
+        cmd = b'\xaa\xb4\x06\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\x05\xab'
+        uart.write(cmd)
+        header = uart.read(1)
+        if header == b'\xaa':
+            command = uart.read(1)
+            if command == b'\xc5':
+                AWAKE = False
+    print('sds011 successfully put to sleep')
+
+def process_packet(packet):
+    try:
+        print('\nPacket:', packet)
+        *data, checksum, tail = struct.unpack('<HHBBBs', packet)
+        pm25 = data[0]/10.0
+        pm10 = data[1]/10.0
+        # device_id = str(data[2]) + str(data[3])
+        checksum_OK = checksum == (sum(data) % 256)
+        tail_OK = tail == b'\xab'
+        packet_status = 'OK' if (checksum_OK and tail_OK) else 'NOK'
+        print('PM 2.5:', pm25, '\nPM 10:', pm10, '\nStatus:', packet_status)
+        mqtt.publish({
+            'pm25': pm25,
+            'pm10': pm10,
+            'status': packet_status
+        })
+    except Exception as e:
+        print('Problem decoding packet:', e)
+        sys.print_exception(e)
+
+def read(allowed_time):
+    global uart
+    print('Reading from sds011 for', (allowed_time / 1000), 'secs')
+    start_time = time.ticks_ms()
+    SHOULD_READ = True
+    while SHOULD_READ:
+        try:
+            delta_time = time.ticks_diff(time.ticks_ms(), start_time)
+            if (delta_time > allowed_time): SHOULD_READ = False
+            header = uart.read(1)
+            if header == b'\xaa':
+                command = uart.read(1)
+                if command == b'\xc0':
+                    packet = uart.read(8)
+                    process_packet(packet)
+        except Exception as e:
+            print('Problem attempting to read:', e)
+            sys.print_exception(e)