Post by thread:[PIC]:18F compare routines

antoniasse wrote: > I need to make a 16bit number compares A<B, A>B, A<=B ,A>=B. > > Have somebody got it in asm code for the 18F series > to help me? I don't, but given that the 18F has a subtract with borrow instruction, this should be easy to do yourself. ****************************************************************** Embed Inc, Littleton Massachusetts, (978) 742-9014. #1 PIC consultant in 2004 program year. http://www.embedinc.com/products

antoniasse wrote : > Subject: [PIC]:18F compare routines Why not simply use the 18F compare *instructions* ? Note that in most cases it's enough to compare the high bytes of the 16 bit numbers, only if they are equal you have to compare the low bytes. Depending on which of the operations you are doing, of course. Jan-Erik.

Thanks Jan-Erik You are right, I´ve got it using the 18F compare instructions. I did a mistake, because I´ve been using to 16F series. I also tried to do this using subtract with borrow instruction, but I could not make it work. Best Regards Luis F. {Quote hidden}> antoniasse wrote : > > >> Subject: [PIC]:18F compare routines > > Why not simply use the 18F compare *instructions* ? > > Note that in most cases it's enough to compare > the high bytes of the 16 bit numbers, only if they > are equal you have to compare the low bytes. > Depending on which of the operations you are > doing, of course. > > Jan-Erik. > > > > -

I tried to fix it using 18F compares instructions and I didn't like of the result. I will continue using like a 16F series that has worked. See below: RAM >= X RAM <= X movlw XL movf RAML,W subwf RAML,W sublw XL movlw XH movf RAMH,W btfss STATUS,C btfss STATUS,C addlw 1 addlw 1 subwf RAMH,W sublw XH btfsc STATUS,C btfsc STATUS,C bra TRUE bra TRUE I thought that would spend less codes using the 18F instructions to make it in a 16bit number. Luis F. {Quote hidden}> > Thanks Jan-Erik > You are right, I´ve got it using the 18F compare instructions. > I did a mistake, because I´ve been using to 16F series. > I also tried to do this using subtract with borrow instruction, but > I could not make it work. > > Best Regards > > Luis F. > > > >> antoniasse wrote : >> >> >>> Subject: [PIC]:18F compare routines >> >> Why not simply use the 18F compare *instructions* ? >> >> Note that in most cases it's enough to compare >> the high bytes of the 16 bit numbers, only if they >> are equal you have to compare the low bytes. >> Depending on which of the operations you are >> doing, of course. >> >> Jan-Erik. >> >> >> >> --