CC2640R2F: CC2640R2

Which clock frequency are you referring to? Are you referring to the clock frequency CC2640R2 uses?

Thank you for your reply,

yes, i'm referring to the clock frequency of CC2640R2 , for Simple_Peripheral SDK example.

This line from section 1.3 in the CC2640R2 datasheet should answer your question:
"The SimpleLink Bluetooth low energy CC2640R2F device contains a 32-bit ARM® Cortex® -M3 core that runs at 48 MHz"

The CC2649R2 uses a 24 MHz xtal, this clock is x2 before it's used internally.

If i want to reduce the frequency in Simple_Peripheral SDK example to 4MHz , where i have to modify.

Please let me know.

Thanks & regards

~Sretha