merge_words_into_long and split_long_into_words operations in Spin

youngdave

Dear All
I have an array of word variables. I need to select two of these words according to criteria C, combine them in a temporary long variable, rotate that long left by X bits, and then split that long back into two words.
Anyone have any ideas on how to do merge_words_into_long and split_long_into_words operations in Spin?
TIA David Young

localroger

There are several ways. What I would do is reference word[noparse][[/noparse]@var] and word[noparse][[/noparse]@var+2] wher var is the long. In spin you can do that both for reading and assignment.

ericball

localroger said...
There are several ways. What I would do is reference word[noparse][[/noparse]@var] and word[noparse][[/noparse]@var+2] wher var is the long. In spin you can do that both for reading and assignment.

Or word[noparse][[/noparse]@longvar][noparse][[/noparse]0] and word[noparse][[/noparse]@longvar][noparse][[/noparse]1].· Just remember the propeller is little endian, so word[noparse][[/noparse]@longvar][noparse][[/noparse]1] is the most significant bits in the long.· And code the variable as a LONG which you access as two WORDs rather than two WORDs which you try to access as a LONG - in order to ensure the variable is LONG aligned.

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Post Edited (ericball) : 8/10/2009 12:30:39 PM GMT

youngdave

Thanks very much for the ideas.
David Young