> On Tue, 25 Jan 2005 13:20:44 -0500, Bob Ammerman wrote:
>>
>>     movlw    (1<<FLAG_Happy)|(1<<FLAG_Sleepy)|(1<<FLAG_Doc)
>>     iorwf    FLAGS,f
>
> I can't for the life of me see what you're doing with this one (I must be 
> getting old! :-) - care to explain?
>
> Cheers,
>
>
> Howard Winter
> St.Albans, England

Sure:

The expression

 (1<<FLAG_Happy)|(1<<FLAG_Sleepy)|(1<<FLAG_Doc)

Is computed at assembly time. Each component of the form

1<<FLAG_Xxxxx

evaluates to a single one bit, shifted to the correct location for the 
corresponding flag.

Thus

(1<<FLAG_Happy)|(1<<FLAG_Sleepy)|(1<<FLAG_Doc)

is a value with the three flag bits set, and all the other bits clear.

Then the IORWF turns on all three flag bits at once.

Bob Ammerman
RAm Systems


-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist