Pic24f read-after-write (stall case)

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mandarsansare

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deviceIC24FJ256GB110

I am not getting the highlighted part. Why it is "Allowed"?????

Ref manual says:

Read-After-Write Dependency Rules If a working register, Wn, is used as a write operation destination in the current instruction, and the same working register, Wn, being read in the prefetched instruction are the same, the following rules will apply: 1. If the destination write (current instruction) does not modify the contents of Wn, no stalls will occur; or 2. If the source read (prefetched instruction) does not calculate an EA using Wn, no stalls will occur.

Any kind of help is appreciated!!! Thank You
 

The device manual paragraph "Read-After-Write Dependency Rules" is describing operations that will automatically take place during program execution. You don't need to take care of it, except if you are calculating cycle accurate execution times or consider how to optimize instruction flow when writing assembler code (I guess you don't).

What are you trying to achieve?
 

I am studying PIC24F for my future projects. I was reading datasheets and Ref. manuals....so this doubt came.
I m not trying to achieve anything regarding RAW dependency ....just I was curious to know..
 

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