class GatewayInterface:
def __init__(self, port, queue):
import sys
sys.path.append('.\pycrc-0.7.7')
import threading
from crc_algorithms import Crc
import serial
self.xport_serial = serial.Serial(port, 115200, timeout=5.0)
self.crc = Crc(width = 16, poly = 0x1021, reflect_in = True, xor_in = 0xffff, reflect_out = False, xor_out = 0x0000)
self.reading = threading.Event()
"""
We spawn a new thread for the worker.
"""
self.queue = queue
# Set up the thread to do asynchronous I/O
# More can be made if necessary
self.running = 1
self.thread1 = threading.Thread(target=self.worker_thread)
self.thread1.start()
def stop(self):
self.running = 0
self.reading.wait(5.0)
self.xport_serial.close()
def get_msg(self, queue):
self.reading.clear()
raw_msg = bytearray()
raw_msg.extend(self.xport_serial.read(1))
if len(raw_msg) > 0:
print("MSG RECV", raw_msg[0])
try:
msg = msg_id_dict[raw_msg[0]]()
except KeyError:
print("Unkown msg", raw_msg[0])
else:
#Success
raw_msg.extend(self.xport_serial.read(1))
raw_msg.extend(self.xport_serial.read(raw_msg[1]-2))
#parse msg
msg.parse_raw(raw_msg)
#remove crc bytes for end of raw and then calc crc
calc_crc = self.crc.bit_by_bit_fast_array(raw_msg[0:len(raw_msg) - 2])
#response
resp_msg = bytearray(2)
resp_msg[0] = 0x80 | raw_msg[0]
if(calc_crc == msg.recv_crc):
resp_msg[1] = 0xA5
queue.put(msg)
else:
print("CRC fail")
resp_msg[1] = 0x00
#send resp is expected
if(msg.Response() == True):
write_len = self.xport_serial.write(resp_msg)
print("RESP_MSG: len", len(resp_msg), write_len, resp_msg)
self.reading.set()
return True
self.reading.set()
return False
def worker_thread(self):
"""
This is where we handle the asynchronous I/O. For example, it may be
a 'select()'.
One important thing to remember is that the thread has to yield
control.
"""
while self.running:
if self.get_msg(self.queue) == False:
print("Timeout waiting for read")
"""
