I need answer for strange situation which occurs sometimes when I jamming the GSM.
I set JDR by AT#JDR=2,70,5 command
I start jamming.
I run “test()” in while with “cmd” = “+CREG?”
The “print s” result contain information about jammer and CREG but why the CREG “\r\nOK\r\n” was printed as “\r\nO” and “K\r\n”.
How to prevent for this?
Below code for test:
_STOP = “\r\nOK\r\n”
_ERROR = “\r\nERROR\r\n”
def test(cmd):
if MDM.send(“AT%s\r” % (cmd, ), 20) == -1:
raise IOError, “\r\nAT%s” % (cmd, )
l = “”
stop = None
while not stop:
s = MDM.receive(51)
print s # Test point
l = “%s%s” % (l, s)
if l.find(_STOP) != -1:
stop = 0xFF
s = _STOP
elif l.find(_ERROR) != -1:
stop = l
s = _ERROR
ans = 0
The return value will be the first string received no matter the timeout value.
If you want to ensure all data is received is better to implement a read routine based on 2 exit conditions, a group of expected characters and a max timeout, like below:
def Chat(command, expected, timeout): timer = MOD.secCounter() + timeout MDM.send(command, 5) b = command + MDM.read() while (MOD.secCounter() < timer) and (b.find(expected) == -1): b = b + MDM.read() return b
If you want to ensure all data is received is better to implement a read routine based on 2 exit conditions, a group of expected characters and a max timeout, like below: