Hi,
I’m trying to do a project where I send/receive data using a GM862 as a GPRS modem (e.g. the device outputs data at some frequency, and a command can be sent from the server to the device to tell it what data to send). From what I read in the documentation, however, the GM862 only supports one socket at a time. I am under the impression that it takes a significant amount of time to open/close a socket and send data, so alternating is out of the question - not to mention the fact that in many cases, there won’t be a request to change the data sent.
Is there any way to have a bidirectional socket? Otherwise, I was thinking I could do an HTTP POST to a PHP script and read the file to get the list of parameters to report (requires a lot of processing), or to send an SMS when the data output must be changed (might not be fast enough).
Anyone have experience with this? A sample AT command set? It would be much appreciated.
A bit of a followup: I was planning on utilizing TCP since I would rather not miss any data if possible. I understand the GM862 retransmits packets that don’t “make it,” but what about reconnecting if signal is lost? Does it transmit the buffer, dump the data, etc.? I don’t know how much error handling I’ll have to do on my end - or if the socket really is persistent.
Thanks in advance!