Re: To transmit text message in different language from pic with sim800
Can we assume that you are talking about SMS messages ?
It's rather unclear what you (or better your receiver) intend to do with these SMS messages.
Who will be the recipient and who should be able to read it ? (Human User, which Devices, Software only?)
You cannot just send some effectively binary data, you must adhere to SMS standards. You did not specify what your "12 bit serial UNICODE" exactly should be.
See your SIM800 AT+CMGF command which may select either Text mode or PDU mode, as Katela proposed.
Your original question how to transfer 12 bit data over UART does not yet make sense without further background information.