Assembler question: order of registers in AND

sanandak

I am reading an input pin and this works:

and Pin, ina nr, wc

but this doesn't:

and ina, Pin nr, wc

I know one can't modify ina, but the nr flag should prevent that, right?

It works, but I'm where else could this be an issue?

Thanks,
S

Lord Steve

The Propeller hardware does not permit INA being in the destination field of the instruction.· It's a instruction set architecture implementation issue, not an effects flag issue.

sanandak

Thanks... I missed that in the documentation.
Sincerely,
Sridhar.

rokicki

Which is why the assembler should warn about this; this happens again and again and will continue to bite people and cause
them frustration that is easily avoided. Give the shadow registers different names (like INA_SHADOW or something) and
let's nip these problems in the bud.

Lord Steve

Actually, that's true.··Is there·reason the assembler can't detect incorrect usage of INA and friends?· Helpful tools are...uh...helpful.

Mike Green

This has come up before. Apparently the assembler doesn't have provisions for warning messages, only "fatal" error messages and, occasionally, the shadow registers are useful. Personally, I would love to see a variety of enhancements to the compiler/assembler including this type of warning and some kind of provision for macro processing like an option or preference that supplies the path and name of a command line program to do preprocessing on each object as it's compiled. The command line program would be executed with the name of the input file and a temporary file to be used for the actual program to be compiled once the "pre-processor" is done. An error return from the preprocessor would abort the compilation.

rjo_

Mike & rokicki,

I think the guys at Parallax have some real tight time constraints... and any time taken to do this would be time taken away from other more pressing matters.
I have a feeling that all of the feedback is being heard, noted and queued, and I would be willing to bet you a fried Prop that these issues will be addressed in the next formal release of new hardware[noparse]:)[/noparse]
I'm having trouble searching things.... I know that the issue of searching has been addressed but when I do a search to find it... I can't.

You guys are the best.

Rich