Post by thread:Greater or less then?

Hello All Some PICs like the 17C766 have >,< and = instructions. If a PIC does not have these instructions can the same opperations somehow be proformed on data. I also have a project that is using A/D conversion if the previous instructions cannot be used what would be the best way proform a function based on the digital data? There are several hundred functions. Thanks Scott

The basic way to do greater than, less than, etc. is to do comparisons; One warning; Make sure you don't switch the logic up of the compare (From doing LOTS of software testing and catching my own, mmm, "RARE", bugs, this is a VERY popular mistake. Macros or a "cheat file" are good here.) Basic method depends on your quantities you're comparing (32 bit? 4 bit? <G>) so I'm using pseudocode here, sort of. Basically, to do "if (A > B) goto GT else goto LE", do this; Reg=A-B if (Reg negative) goto LE /*Usual test people mess up on.*/ if (Reg zero) goto LE goto GT Alternately, less code but perhaps less clear - More "optimized": Reg=B-A if (Reg negative) goto GT /*Usual test people mess up on.*/ /*Treat Zero as 'positive' here.*/ goto LE This should help, I hope <G> Mark Scott Beatty wrote: {Quote hidden}> > Hello All > > Some PICs like the 17C766 have >,< and = instructions. If a PIC > does not have these instructions can the same opperations somehow be > proformed on data. I also have a project that is using A/D conversion > if the previous instructions cannot be used what would be the best way > proform a function based on the digital data? There are several hundred > functions. > > Thanks > Scott -- I re-ship for small US & overseas businesses, world-wide. (For private individuals at cost; ask.)

I didnt keep the original message so the thread doesnt really work here I found a nice page for your 8 bit compares it has all forms you could ask for .... websites.ntl.com/~matthew.rowe/micros/virbook/logic.htm It has routines from Andrew Warren The root page http://websites.ntl.com/~matthew.rowe/micros/ has even more interresting pic information Scott Beatty (spam_OUTspamdoggTakeThisOuTwebbernet.net) wrote: Hello All Some PICs like the 17C766 have >,< and = instructions. If a PIC does not have these instructions can the same opperations somehow be proformed on data. I also have a project that is using A/D conversion if the previous instructions cannot be used what would be the best way proform a function based on the digital data? There are several hundred functions. Thanks Scott