How to transmit GPS data to GSM using 16F84A

[syide]

Hello, i am student now working with my final year project.

I am doing vehicles position and speed tracking.My problem now is i dun know how to transmit GPS data to GSM module(or 3G module) using PIC.Can anyone give me an idea.

Through my reading i understand PIC can read data from GPS using NMEA protocol.Then how to transmit this data to GSM module. pleazzzzz help.

Thank u

 

[Diver300]

It depends what you want to transmit the data to.

If you get a GSM module such as a GE864 https://www.telit.com/en/products/gsm-gprs.php?p_id=12&p_ac=show&p=4 you can send and receive texts or you can use GPRS to send data to a web server, or send emails.

I think that you can connect to some ordinary mobile phones, which might be cheaper.

The 16F84A is a poor choice of processor. The 16F627A does more and is cheaper but is still not enough for what you want.

I suggest that you go for something much more powerful. For one thing, you have two data streams to deal with (GPS data and GSM data) and so two EUSARTS makes things a lot easier. Without two EUSARTS, you still have to be able to receive data from both the GPS and the GSM, so your program timing becomes very difficult.

Also, you may want a lot of data. The 16F84A has 68 registers. A text message is up to 160 characters long, and you need a phone number to send it to.

If you have GPRS connection you need to tell the phone the access point name and that is often 20 characters long.

I write the software for the vehicle trackers at www.on-trak.co.uk and I use a pic24FJ64GA004. Programmed in assembly, it's got about half the program space used, but it does do lot more than you need.

In a prototype, I did get a text message using a pic16F688 but it was very limited for program and register space.

I suggest a PIC24FJ64GA002 as you can get that in DIP so you can put it in a socket.

 

[syide]

Can u explain to me bout how many character can we put in one register??

 

[blueroomelectronics]

ASCII generally 1 byte, packed BCD (00-99) can fit in one byte.

 

[Diver300]

As blueroomelectronics says, I character fits in 1 byte of memory.

The normal characters used in texts (A-Z, a-z, 0-9 and normal punctuation) is 7 bits of information (128 possibilities) and it is usual to put those 7 bits in one register which is 8 bits.

Two digits of decimal (0-9) or hexadecimal (0-9, A-F) which are 4 bits each can also fit in one 8 bit register.

When you send a text with a GSM phone, you have to tell it the phone number (11 digits or so) and what you want to send (up to 160 characters). That has to be programmed into the PIC, and debugged. It is easiest to prepare the whole lot in the registers of the PIC then send it. That way you can debug the prepare routine using MPLAB simulator before you have to worry about timing and sending one character (or 1 bit if you haven't got enough EUSARTS) at a time.

It is so much easier if you can use 200 registers for the message. Get yourself a PIC with plenty of program and register spave. It is still virtually free compared to the GSM phone, the GPS, the battery or power supply and your time.

 

[rainCheck]

phone GSM

Hi
i'm in oz and GSM modules are neither cheap nor easy to find, most are sold in bulk i only want one!!!
does anyone know hot to hack the module out of a phone? i know i may use F-bus on some nokias, but i had trouble finding the complete F-bus command set. does anyone know what phone/protocol i may use?
ANY help greatly appreciated!

 

[syide]

I know wat u mean now.Thnks for the explanation.

I want ur help to show me the way to do vehicle trackers.If there is any circuit or coding i can refer to give me better understand?

 

[Diver300]

ELEKTOR.com - electronics worldwide has an article in this month's magazine about connecting a GSM phone and a GPS receiver.

Mobile phones are made with chips directly on the circuit board. They do not contain separate phone modules. Phone modules are only used in larger devices that aren't made in such quanities.