Re: 16f84 by keil
yes you need to go for some other IDE like keil.
eg.
1.HI-TECH PICC STD compiler supports all currently available Microchip PIC10/12/14/16/17 series microcontrollers with additional support for new Microchip PICmicro devices available as they are released.
Integrated Development Environment
HI-TECH PICC STD can be run entirely from the Integrated Development Environment (HI-TIDE™ 3). This environment allows you to manage all of your PIC projects. You can compile, assemble and link your embedded application with a single step.
2. MIKRO-C,
3. HI-tech C are few compilers