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• RP2040l + wifi, micropython
• Smartphone OS iOS
• Blynk server
• Blynk Library version
• Add your sketch code.
Code should be formatted as example below.
Hi. Using Blynk for the first time. Using micropython with uasyncio.
I have this working great: blynk.virtual_write(1, water_temp) and it updates the Blynk dashboard.
But I am having problems reading data from the dashboard and using it in my micropython code. For example, I set a switch up on the Blynk App and I want to read the switch state in my micropython code.
I would like to go: switch_state = blynk.virtual_read(2)
But it is not that simple! I am using the below Blynk library (works great to write info to the app - and working with uasyncio)
__version__ = "1.0.0"
import struct
import time
import sys
import os
import uasyncio
try:
import machine
gettime = lambda: time.ticks_ms()
SOCK_TIMEOUT = 0
except ImportError:
const = lambda x: x
gettime = lambda: int(time.time() * 1000)
SOCK_TIMEOUT = 0.05
def dummy(*args):
pass
MSG_RSP = const(0)
MSG_LOGIN = const(2)
MSG_PING = const(6)
MSG_TWEET = const(12)
MSG_NOTIFY = const(14)
MSG_BRIDGE = const(15)
MSG_HW_SYNC = const(16)
MSG_INTERNAL = const(17)
MSG_PROPERTY = const(19)
MSG_HW = const(20)
MSG_HW_LOGIN = const(29)
MSG_EVENT_LOG = const(64)
MSG_REDIRECT = const(41) # TODO: not implemented
MSG_DBG_PRINT = const(55) # TODO: not implemented
STA_SUCCESS = const(200)
STA_INVALID_TOKEN = const(9)
DISCONNECTED = const(0)
CONNECTING = const(1)
CONNECTED = const(2)
print("""
___ __ __
/ _ )/ /_ _____ / /__
/ _ / / // / _ \\/ '_/
/____/_/\\_, /_//_/_/\\_\\
/___/ for Python v""" + __version__ + " (" + sys.platform + ")\n")
class EventEmitter:
def __init__(self):
self._cbks = {}
def on(self, evt, f=None):
if f:
self._cbks[evt] = f
else:
def D(f):
self._cbks[evt] = f
return f
return D
def emit(self, evt, *a, **kv):
if evt in self._cbks:
self._cbks[evt](*a, **kv)
class BlynkProtocol(EventEmitter):
def __init__(self, auth, tmpl_id=None, fw_ver=None, heartbeat=50, buffin=1024, log=None):
EventEmitter.__init__(self)
self.heartbeat = heartbeat*1000
self.buffin = buffin
self.log = log or dummy
self.auth = auth
self.tmpl_id = tmpl_id
self.fw_ver = fw_ver
self.state = DISCONNECTED
self.connect()
def virtual_write(self, pin, *val):
self._send(MSG_HW, 'vw', pin, *val)
def send_internal(self, pin, *val):
self._send(MSG_INTERNAL, pin, *val)
def set_property(self, pin, prop, *val):
self._send(MSG_PROPERTY, pin, prop, *val)
def sync_virtual(self, *pins):
self._send(MSG_HW_SYNC, 'vr', *pins)
def log_event(self, *val):
self._send(MSG_EVENT_LOG, *val)
def _send(self, cmd, *args, **kwargs):
if 'id' in kwargs:
id = kwargs.get('id')
else:
id = self.msg_id
self.msg_id += 1
if self.msg_id > 0xFFFF:
self.msg_id = 1
if cmd == MSG_RSP:
data = b''
dlen = args[0]
else:
data = ('\0'.join(map(str, args))).encode('utf8')
dlen = len(data)
self.log('<', cmd, id, '|', *args)
msg = struct.pack("!BHH", cmd, id, dlen) + data
self.lastSend = gettime()
self._write(msg)
def connect(self):
if self.state != DISCONNECTED: return
self.msg_id = 1
(self.lastRecv, self.lastSend, self.lastPing) = (gettime(), 0, 0)
self.bin = b""
self.state = CONNECTING
self._send(MSG_HW_LOGIN, self.auth)
def disconnect(self):
if self.state == DISCONNECTED: return
self.bin = b""
self.state = DISCONNECTED
self.emit('disconnected')
def process(self, data=None):
if not (self.state == CONNECTING or self.state == CONNECTED): return
now = gettime()
if now - self.lastRecv > self.heartbeat+(self.heartbeat//2):
return self.disconnect()
if (now - self.lastPing > self.heartbeat//10 and
(now - self.lastSend > self.heartbeat or
now - self.lastRecv > self.heartbeat)):
self._send(MSG_PING)
self.lastPing = now
if data != None and len(data):
self.bin += data
while True:
if len(self.bin) < 5:
break
cmd, i, dlen = struct.unpack("!BHH", self.bin[:5])
if i == 0: return self.disconnect()
self.lastRecv = now
if cmd == MSG_RSP:
self.bin = self.bin[5:]
self.log('>', cmd, i, '|', dlen)
if self.state == CONNECTING and i == 1:
if dlen == STA_SUCCESS:
self.state = CONNECTED
dt = now - self.lastSend
info = ['ver', __version__, 'h-beat', self.heartbeat//1000, 'buff-in', self.buffin, 'dev', sys.platform+'-py']
if self.tmpl_id:
info.extend(['tmpl', self.tmpl_id])
info.extend(['fw-type', self.tmpl_id])
if self.fw_ver:
info.extend(['fw', self.fw_ver])
self._send(MSG_INTERNAL, *info)
try:
self.emit('connected', ping=dt)
except TypeError:
self.emit('connected')
else:
if dlen == STA_INVALID_TOKEN:
self.emit("invalid_auth")
print("Invalid auth token")
return self.disconnect()
else:
if dlen >= self.buffin:
print("Cmd too big: ", dlen)
return self.disconnect()
if len(self.bin) < 5+dlen:
break
data = self.bin[5:5+dlen]
self.bin = self.bin[5+dlen:]
args = list(map(lambda x: x.decode('utf8'), data.split(b'\0')))
self.log('>', cmd, i, '|', ','.join(args))
if cmd == MSG_PING:
self._send(MSG_RSP, STA_SUCCESS, id=i)
elif cmd == MSG_HW or cmd == MSG_BRIDGE:
if args[0] == 'vw':
self.emit("V"+args[1], args[2:])
self.emit("V*", args[1], args[2:])
elif cmd == MSG_INTERNAL:
self.emit("internal:"+args[0], args[1:])
elif cmd == MSG_REDIRECT:
self.emit("redirect", args[0], int(args[1]))
else:
print("Unexpected command: ", cmd)
return self.disconnect()
import socket
class Blynk(BlynkProtocol):
def __init__(self, auth, **kwargs):
self.insecure = kwargs.pop('insecure', False)
self.server = kwargs.pop('server', 'blynk.cloud')
self.port = kwargs.pop('port', 80 if self.insecure else 443)
BlynkProtocol.__init__(self, auth, **kwargs)
self.on('redirect', self.redirect)
def redirect(self, server, port):
self.server = server
self.port = port
self.disconnect()
self.connect()
def connect(self):
print('Connecting to %s:%d...' % (self.server, self.port))
s = socket.socket()
s.connect(socket.getaddrinfo(self.server, self.port)[0][-1])
try:
s.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
except:
pass
if self.insecure:
self.conn = s
else:
try:
import ussl
ssl_context = ussl
except ImportError:
import ssl
ssl_context = ssl.create_default_context()
self.conn = ssl_context.wrap_socket(s, server_hostname=self.server)
try:
self.conn.settimeout(SOCK_TIMEOUT)
except:
s.settimeout(SOCK_TIMEOUT)
BlynkProtocol.connect(self)
def _write(self, data):
#print('<', data)
self.conn.write(data)
# TODO: handle disconnect
async def run(self):
data = b''
while True:
try:
data = self.conn.read(self.buffin)
#print('>', data)
except KeyboardInterrupt:
raise
except socket.timeout:
# No data received, call process to send ping messages when needed
pass
except: # TODO: handle disconnect
return
self.process(data)
await uasyncio.sleep_ms(10)