pySerial getting writeTimeout when sending an sms

[Andelys]

Hi,

I'm getting a writeTimeout on a serial connection using pyserial here is my code.

ser = serial.Serial('COM10',
                        baudrate=115200,
                        timeout=2,
                        writeTimeout = 2,
                        bytesize=serial.EIGHTBITS,
                        parity=serial.PARITY_NONE,
                        stopbits=serial.STOPBITS_ONE)
ser.flushOutput()
ser.flushInput()

print "PDU LENGTH", pdu.length # the length of the pdu
ser.write('AT+CMGS=%d\r' % pdu.length)
print ser.readlines()
time.sleep(1)
# write the PDU and send a Ctrl+z escape
print "PDU", pdu.pdu # the pdu string
ser.write('%s\x1a' % pdu.pdu) # this i about where my app stops and throws a writeTimeout
print "sent pdu"
time.sleep(1)
print ser.readlines()

the error i get is:

Traceback (most recent call last):
  File "C:\Users\Andreas\Documents\My Dropbox\Programmering\Projects\SMSTerminal\src\SMSSender.py", line 52, in <module>
    send_text('41603627', 'r'*200)
  File "C:\Users\Andreas\Documents\My Dropbox\Programmering\Projects\SMSTerminal\src\SMSSender.py", line 36, in send_text
    ser.write('%s\x1a\r' % pdu.pdu)
  File "c:\Python26\lib\site-packages\serial\serialwin32.py", line 260, in write
    raise writeTimeoutError
serial.serialutil.SerialTimeoutException: Write timeout

I have tried to extent both the write and the read timeout without any luck

Have anybody experienced the same problem?

i have tried the same commands in hyperterminal and it works.



Andreas

[dwblas]

ser = serial.Serial('COM10',

Do you have 10 serial ports? Also, pyserial uses either
ser = serial.Serial(0 ) # open first serial port
or
ser = serial.Serial('/dev/ttyS0')
AFAIK
In addition you should check for a connect with either of these statements
print ser.portstr # check which port was really used
print ser.isOpen()

[Andelys]

thank you for answering, and yes. When i connect my cellphone to my usb it get 2 serial port and i have connect a couple of them by now and it just count up every time, not the problem.

The port is open, because i am able to send the first command, but when i try to send the pdu which is about 200 chars long it throws a write error. I tried the exact same in Hyperterminal and it works in hyper terminal.

Anyway thanks for your quick reply :)

[dwblas]

I would add a print statement for the length and type, and send the CTRL-Z separately to isolate everything.

print "PDU", pdu.pdu # the pdu string
print len(pdu.pdu), type(pdu.pdu)
ser.write('%s' % pdu.pdu) # this i about where my 
print "pdu.pdu sent"
ser.write('\x1a')