CMPSUB oddity

BradC

This is an odd one...

The manual lists CMPSUB as having the R bit clear by default, meaning it won't write the result.
The compiler sets the R bit by default and requires an "nr" effect to clear it..

        org
        cmpsub a,b
a long 0
b long 0

generates. E0 BC 04 03
with the "nr" it generates E0 3C 04 03 .. as it should..

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Pull my finger!

CJ

I suspect the manual is where the error is, as without the r bit set it is no longer a cmpsub and becomes a compare only

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kuroneko

It's definitely a documentation issue. The "Propeller Manual" lists it as not-written, the "Quick Reference" and the Prop datasheet as written.

mirror

If you download the errata for the manual, then you'll find the correction to this and several other items of error in the Propeller Manual.

http://www.parallax.com/Portals/0/Downloads/docs/prod/prop/PMv1.0Supplement-v1.3.pdf
·

BradC

Thanks for the pointer mirror, the errata documents every other oddity I've picked up thus far..
I wonder if there is any plan to fold this stuff into a manual revision ?

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Pull my finger!

Steph Lindsay

BradC said...
Thanks for the pointer mirror, the errata documents every other oddity I've picked up thus far..
I wonder if there is any plan to fold this stuff into a manual revision ?

Yes indeed there is! The author is writing additions and corrections at this very moment, and work on the production files is scheduled to begin in a few weeks.·If you have any feedback that has NOT been addressed in the Supplement & Errata, please send it to me at editor@parallax.com.

Thanks much,

-Stephanie Lindsay
Editor, Parallax Inc.