hi libin
i am working on a project ,i think it is very similar with your goal
i want to send some datas from gprs modem to a web page via post method in http protocol
i think its better to divide this to some steps:
in first steps: we must choose a platform,gprs&gps module,mcu type& compiler/IDE.
my choise is stm32f103(32bit arm cortex low cost mcu),sim908,keil
in step 2:its better to buy a minimum board for gprs modem & mcu to saving time(at least we can design our pcb for redusing size & customizing it )
in step3: we must collect location coordinates (its not common between us,i dont need location coordinates i only need datas recieved from sencor )
in step 4: we must send datas(location coordinates or sencors amount) to the server,it can be done with http protocol
via post method(module support completely from http)
in step 5: we must design a simple web page for displaying incoming datas
in step 6:when we receive datas successfully we can improve web pages with processing datas,saving & loading
or even display location with google map API
in last step: we must design a good small pcb for it
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its interesting im electronic student and new bie to web programming : )
if you agree i will do electronic section (pcb designing and mcu programming) and you design and program server side (web page )
with best regard