*******************************

* convert a null terminated string to all lowercase

* OTHER MODULES NEEDED: TO_LOWER

* ENTRY: X=start of string

* EXIT:  all registers  preserved

 nam Convert String to Lowercase
 ttl Assembler Library Module

 psect TO_LOWRS,0,0,0,0,0

TO_LOWRS:
 pshs cc,b,x

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

exit
 puls cc,b,x,pc

 endsect