Application Note
Using GPRS and TCP-IP with
the SEM GSM modules
Страница 1: ...Application Note Using GPRS and TCP IP with the SEM GSM modules...
Страница 2: ...Mobile Communications reserves the right to make modifications additions and deletions to this manual due to typographical errors inaccurate information or improvements to programs and or equipment at...
Страница 3: ...GPRS NETWORK 5 2 3 APN 5 2 4 DHCP SERVER 5 2 5 INTERNET 5 2 6 WEB SERVER 5 3 MODES OF OPERATION 7 3 1 GSM MODULES WITHOUT TCP IP STACKS 7 3 1 1 Running GPRS through Windows 7 3 2 GSM UNITS WITH TCP U...
Страница 4: ...e internet enabling M2M applications to interface to web servers rather than going through the PSTN which gives faster and cheaper communications with greater flexibility This document is intended to...
Страница 5: ...S call to The service provider is able to attach anything to an APN to create a VPN Virtual Private Network i e if a security company wanted its own APN it might have security no one else would then h...
Страница 6: ...Using GPRS and TCP IP stack with SEM GSM modules LZT 123 7699 R1A 6 Figure 1 GSM GPRS...
Страница 7: ...dcont command i e at cgdcont 1 IP internet This hold the necessary information required to make a GPRS call 2 Make a GPRS call using the standard dial command but using the dial string 99 1 3 Once the...
Страница 8: ...s the most common errors are Error 738 The most common cause of this error is that the SIM does not have access rights to the internet DHCP server and it is unable to allocate the unit an IP address E...
Страница 9: ...ly allocated i e each time you start a new session the unit will be assigned a new IP address A session may be finished for a number of reasons The unit is powered off and then back on again There has...
Страница 10: ...en below TCP This provides a reliable connection to another point in the network i e numbers frames and keeps track of acknowledgements UDP This is a fire and forget protocol normally used with time c...
Страница 11: ...sential technical background for anyone requiring a deeper understanding of TCP IP A small sample of the more pertinent RFC s and their titles are outlined below but many more are available 1 RFC 791...