view lib/alib/to_upprs.as @ 3278:ea1afb494127

defs: Add Bt.Sec for atari and corsham
author Tormod Volden <debian.tormod@gmail.com>
date Sat, 07 Mar 2020 23:52:40 +0100
parents 03f26e88b809
children
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* convert a null terminated string to all uppercase

* OTHER MODULES NEEDED: TO_UPPER

* ENTRY: X=start of string

* EXIT:  all registers (except CC) preserved


 nam Convert String to Uppercase
 ttl Assembler Library Module


 section .text

TO_UPPRS:
 pshs cc,b,x

loop
 ldb ,x get char to check
 beq exit exit if all done
 lbsr TO_UPPER convert to upper 
 stb ,x+ put back in string
 bra loop

exit
 puls cc,b,x,pc

 endsect