I am trying to connect to 5 different CR1000 dataloggers that are using a COM111 modem with a GSM communication. I am using a '56K USB Dial-up and Fax Modem - V.92' that uses a Conexant - CX93010-21Z chip. Using the USB modem connected to my PC I have been able to send fax and make calls but not to connect to the dataloggers. I am using LoggerNet for the communication to the dataloggers.
I tryed to use the LoggerNet Terminal Emulator and call the loggers but I always get as a reply that the number is BUSY or NO CARRIER, as you can see below. This is not true as I know that the loggers are working and sending data. If I send the same commands using my personal phone number I receive a call so I deduce that the modem is able to call also the loggers but for a reason that I can't understand is then not able to connect to them.
Any help and suggestions would be very appreciated. Thanks.
T: 15:42:46.574 AT&F.
R: 15:42:46.578 ..OK..AT&F...OK.
T: 15:42:48.566 ATS95=1+MS=V32,1,1200,9600;V1.
R: 15:42:48.570 ATS95=1+MS=V32,1,1200,9600;V1...OK..
T: 15:42:48.582 ATDT######### (# is the number I am dialling)
R: 15:42:48.586 ATDT########
R: 15:42:59.085 ..BUSY..
T: 15:42:59.085 +++
R: 15:42:59.101 +++
T: 15:43:32.716 ATH.
R: 15:43:32.727 ATH...OK..
Hi,
it often happens to me that I am unable to call cell phones from landlines, it is a strange thing that for years I still cannot understand (unfortunately the GSM operators do not understand or don't help you).
Some my stations are forced to call them from a GSM modem, try it too, at least to understand.
Maybe you can also save money, GSM to GSM calls are often cheaper than FIXED to GSM calls.
Smile
Hi, thanks for your advice. I will try to find a GSM modem and do also this test, but I can call without problem different mobile phones using the modem connected to my PC.
I did some additional tests and now when I call my COM111 modem (containing a SIM M2M) I can hear the sound of what I think is a data connection (dial tone followed by a series of beeps and tones, followed by what sounds like white noise or scratching sounds and screeches) but I don't receive a CONNECT reply and the call therefore ends without establishing a connection....I get then a NO CARRIER reply.
Any help and suggestions would be very appreciated. Thanks.
Is this a network that was operating on GSM CSD dialup and has now stopped working?
Many networks are beginning to turn off GSM CSD dialup connections. A customer in Austria recently found his systems could not be connected to and found out that the network operator had stopped the CSD service 2 weeks before. I would check with your network supplier if they still support CSD dialup services.
Thanks nsw for your advice. I checked with my network supplier and CSD dialup is supported.
After trying for 3 weeks I finally got my first connection to one of the loggers yesterday. I managed to connect four times in total between yesterday and today but only for few seconds and after that the connection ended and I couldn't connect anymore. Only one of the four connections lasted long enough for me to download the logger program and 3 days of data. Did someone experience a similar issue?
I am happy that I managed to connect but I do not get why my communication drops and I can't connect anymore after.
Any help and suggestions would be very appreciated. Thanks.
Have you checked the power supply to the system(s) is giving 12V DC and is not dropping off line whent the modem starts communicating?
do these first successful attempts go with GSM to GSM or with fixed to GSM?
Do you know the amount of signal to the remote modem?
locally with a PC connected to the remote modem and a serial terminal, it is possible to use the AT + CSQ command to know the quantity and quality of the GSM signal.
Of course you can also use the logger that bridges the serial port of the PC and the modem with the "through" function in the logger terminal.
Do you use a good antenna for the remote modem?
As already suggested, check the correct 12V power.
It is also useful to switch off the modem from programmed intervals, to verify that the modem registers, they often go off line and it is necessary to switch off and on
A little more complicated can also be done via sw (via specific AT command)
With the sw12 it is easy to turn off and ON the modem every hour (I.E.) to a few seconds.
Smile