time need to execute an instruction

When f=1MHz how much time need exactly to execute a NOP on a PIC16F84 chip? 
(I think 4us but I am not sure)

Thanks
 Attila

John Smith wrote:
> When f=1MHz how much time need exactly to execute a NOP on a PIC16F84 chip? 
> (I think 4us but I am not sure)

According to the data sheet:

All instructions are executed within one single instruction cycle, 
unless a conditional test is true or the program counter is changed as a 
result of an instruction. In this case, the execution takes two 
instruction cycles with the second cycle executed as a NOP. One 
instruction cycle consists of four oscillator periods. Thus, for an 
oscillator frequency of 4 MHz, the normal instruction execution time is 
1 us.

So yes, a NOP takes 4 us.

On 2008-02-12, John Smith <john.smith@hotmail.com> wrote:
> When f=1MHz how much time need exactly to execute a NOP on a PIC16F84 chip? 
> (I think 4us but I am not sure)

Yes.  Except for branches it is 4 clock cycles per instruction so
at 1MHz that would be 4us.

-- 
Andrew Smallshaw
andrews@sdf.lonestar.org