hi,
in my project i have to use 2 uart in 8051 micrcontroller. i am using gsm and gps in my project.my problem is when i receiving gsm sms i have to send gps value to same number . the mobile number is not stored in software.we can receive sms form any mobile number and reply to that number.how to handle this problem? suggest me best thing
Handle what problem?
That you get an SMS from an unknown source and don't want to waste money sending back an answer?
Just require the SMS to contain a known content: "Send GPS". A random SMS will not contain that text, so will not trig any response.
By the way - thread subject is "dual serial communication", but you don't seem to ask any question relating to dual serial ports. So why not a thread title related to your actual problem?