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  1. #1
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    can i interface GPS, GSM and a Memory chip to a single PIC?

    I have planned to impose speed limits in the required zones.. RF method to do this is already available.. But, i wish to do it by trying it with GPS.. the GPS positions of the speed limit zones and also the required speed limits should be stored in the Memory chip ( as a database ).. the GPS position of the running vehicle is continuously monitored and compared with the already available database.. GSM is used for any updatings in the speed limit data... So, i need to interface GPS, GSM and a Memory chip to a PIC microcontroller(16f877a).. Is it possible? how to do it? what all communications should i use for these interfacing modules and what all pins should i use...

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    Re: can i interface GPS, GSM and a Memory chip to a single PIC?

    Is it practical... i understand from your statement should all car have GPS, or how this concept is used in your project... i dont get picture how you can use GSM and GPS for your purpose..........
    " It is so simple to be happy,
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  3. #3
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    Re: can i interface GPS, GSM and a Memory chip to a single PIC?

    GSM and GPS both use UART. So, need PIC with 2 UART.
    PIC16F877A have one UART. It's also possible to do UART software, but it's also difficult. I have tried.
    Easy way, find other PIC with 2 UART.



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    Re: can i interface GPS, GSM and a Memory chip to a single PIC?

    Gokul,

    If you are talking about GPS reception and message send through GSM, you can surely do that with single UART.

    If its receiving and sending messages with GSM and receiving signals via GPS. you can still do that with minor modifications in your hardware, considering the fact that you can either read GSM or GPS and any given point of time not both.

    If you need both and at almost the same time. I suggest you to have a bit bang option using some other IO pin.

    As far as the memory goes, you can use a internal flash or EEPROM. Through your requirement i am guessing that it is more of a engineering project and hence the memory i suggested should be sufficient. If you still need more add a I2C EEPROM.

    All the Best.

    Regards
    Sachin


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    Re: can i interface GPS, GSM and a Memory chip to a single PIC?

    Hi
    Maybe no one has tried bit banging method, and mostly talk based on what they read in books... Its very difficult to get baudrate of 4800 and above... Mainly bit banging is implemented for baud rate less than 600bps.............
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    Re: can i interface GPS, GSM and a Memory chip to a single PIC?

    Shivaram,

    With all due respect to your post. I would like to clarify that we have achieved the baud of 9600 using bitbang. It can surely take some time but if your know the uart operation inside out, it can be done for sure.



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  7. #7
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    Re: can i interface GPS, GSM and a Memory chip to a single PIC?

    thanks sachin... but getting accuracy is a tough task... but do try this concept when you want the ISR to be used.. Without actual hardware this bit banging do not support at higher speeds...
    " It is so simple to be happy,
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    Re: can i interface GPS, GSM and a Memory chip to a single PIC?

    Quote Originally Posted by ckshivaram View Post
    Hi
    Maybe no one has tried bit banging method, and mostly talk based on what they read in books... Its very difficult to get baudrate of 4800 and above... Mainly bit banging is implemented for baud rate less than 600bps.............
    I agree with you. Many people just said it can be done by what they are reading, but less people that actual tried that.
    That is very difficult to get the accuracy for long data transmission. The example exist is only transmit and receive one byte only. I have tried doing bit banging method and I can use baudrate up to 9600 but only can receive up to 6 byte. The bit banging transmit is no problem. In the future, If I can improve for receive many more byte, I will share the code.



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