lpcmanager

Smarteh RS485 bus: Rx timeout changed from 50 ms to 20 ms (slaves answer in approx. 10 ms). Timeout is žset outside while loop because select() decreases timeout gradually.

2017-01-13, bmakuc
bb465ef96b61
Smarteh RS485 bus: Rx timeout changed from 50 ms to 20 ms (slaves answer in approx. 10 ms). Timeout is žset outside while loop because select() decreases timeout gradually.
import serial
import exceptions
from threading import Lock
import time
class LPCProtoError(exceptions.Exception):
"""Exception class"""
def __init__(self, msg):
self.msg = msg
def __str__(self):
return "Exception in PLC protocol : " + str(self.msg)
class LPCProto:
def __init__(self, port, rate, timeout):
# serialize access lock
if BMZ_DBG:
# Debugging serial stuff
self._serialPort = serial.Serial( port, rate, timeout = timeout, writeTimeout = timeout )
class myser:
def readline(self_):
res = self._serialPort.readline()
print 'Recv :"', res, '"'
return res
def read(self_,cnt):
res = self._serialPort.read(cnt)
if len(res) > 16:
print "Recv :", map(hex,map(ord,res[:16])), "[...]"
else:
print "Recv :", map(hex,map(ord,res))
return res
def write(self_, string):
lstr=len(string)
if lstr > 16:
print "Send :", map(hex,map(ord,string[:16])), "[...]"
else:
print "Send :", map(hex,map(ord,string))
return self._serialPort.write(string)
# while len(string)>0:
# i = self._serialPort.write(string[:4096])
# print ".",
# string = string[i:]
# print
#return lstr
def flush(self_):
return self._serialPort.flush()
def close(self_):
self._serialPort.close()
self.serialPort = myser()
else:
# open serial port
self.serialPort = serial.Serial( port, rate, timeout = timeout )
# start with empty buffer
self.serialPort.flush()
def __del__(self):
if self.serialPort:
self.serialPort.close()
def close(self):
self.serialPort.close()
self.serialPort = None