>I am using pic18f452, and i am trying retrieve data from gps
>reciever and then send data using gsm network,  but how i can
>connect both gps and gsm to pic18f452 (serial connection), so
>that the trasmission and reception is done simultaneously
>(for real time application).

There are some 18F pics with 2 UARTS, but I think they are all 44 pin TQFP 
packages, but that may not worry you. Also some of the dsPic devices have 2 
UARTS.

If none of these devices suit, you can do a software UART. The Microchip 
PIC18 C compiler comes with a software UART module as well as a hardware 
UART module. 

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