I want to set the CPU(XTAL) frequency for my microcontroller(LPC2129) in IAR Embedded Workbench IDE, but after lots of search and exploration in IDE, I nowhere found anything related to it. Maybe my question looks so general but it happens to me. Every Embedded IDE/compiler(like Keil, Mikroc, ATMEL Studio) has this CPU frequency set option but in IAR I not know how to set it. Sometimes, I am also guessing that if there is no option in software than there must be some compiler-specific keyword like F_CPU(in ATMEL Studio ) must be there. Please help..Thank you