VT pin of HT12D please help, it' urgent....

[MICRO THOUGHTS]

Hai,
please help me to know about the VT pin of ht12d . i need a 4bit data for feeding pic16f877a.
do i connect vt to the vdd or ground, or not connected anywhere? what about the address pins of ht12d &ht12e, i need to send 4 bit data through a rf transmitter, what is the use of address pins. i am doing my mini project ( water level controll unit) there are 4 levels ( 0%, 25%, 50%, 75%. 100% of water in the tank ie 0001, 0011, 0111, 1111). do any use of address pins in this circuit , if any need to connect these pins to ground or not connect. please help me..........

 

[mister_rf]

The HT12E is capable of encoding information which consists of 8-address bits and either 4 further address/data bits . For the HT12E encoders, transmission is enabled by applying a low signal to the TE pin. If a transmission enable signal is applied, the HT12E encoder scans and transmits the status of the 8 bits of address(A0 – A7) and 4 bits of data (AD8-AD11) serially in the order A0 to AD11. Each address/data input can be set to one of the two logic states. The programmed addresses/data are transmitted together with the header bits via an RF or an infrared transmission medium upon receipt of a trigger signal. Pins 1...8 of encoder are for setting the unique signal and important to set the same pins of decoder with identical settings, otherwise the receiver will not decode the signal.

The HT12D is arranged to provide 8 address bits and 4 data bits and the VT pin goes high to indicate a valid transmission and can be used as a momentary data output.
See the diagram attached: