Bug with low baudrate on serial port

We are using Q26RD with Fw 7.44. The modem is connected to our main device through UART1. Its main functionality is to download (From server to the device) a unique file which size is about 1Mo / 1.5Mo. The trick is that, in this design, we have to use a « low » baudrate between the modem and our main device.

I did a test with this configuration:

  • Developpment kit connected to a PC (HyperTerminal) trough UART1
  • Baudrate on UART1 : 1200
  • No OpenAT application
  • Flux control : Not relevant (I’ve tried with and without)
  • Downloaded file size : 1Mo

After a few bytes received (between 45Ko and 90Ko in my case) the modem resets. I don’t know why : Watchdog or internal buffer overflow ?
Same test with baudrate = 115200 runs perfectly.

Does anyone saw the same behavior? Is that a known bug?
How can I walk around? I’d may reduce the GPRS dataflow but I don’t know how to do so…

Thank’s for help.

Here’s a trace :

at+wipcfg=1
OK
at+wipbr=1,6
OK
at+wipbr=2,6,11,"my_apn"
OK
at+wipbr=2,6,0,"my_login"
OK
at+wipbr=2,6,1,"my_pwd"
OK
AT+WIPBR=2,6,12,1
OK
at+wipbr=4,6,0
OK
AT+WIPCREATE=2,1,"my_ip",my_port
OK
+WIPREADY: 2,1
at+wipdata=2,1,2
CONNECT
<my_http_request>
HTTP/1.1 200 OK
Date: Thu, 28 Apr 2011 06:46:01 GMT
Server: Apache
Last-Modified: Fri, 24 Dec 2010 08:32:48 GMT
ETag: "2000000009649-13d620-49823d4c9643d"
Accept-Ranges: bytes
Content-Length: 1300000
Connection: close
Content-Type: text/plain

/File content/

/Software reset/

Hi
Did you change the baud rate by issuing AT+IPR=1200 command and save it using AT&W command or you just changed the baud rate in the settings of hyperterminal?

Regards
Paruthiv

I’ve changed both and saved with AT&W prior to any test.