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

* See if character in "B" is a control character
* controls are defined as $00..$1F and $7F+

* OTHER MODULES NEEDED: none

* ENTRY: B=character to test

* EXIT: CC zero=1 if control, 0 if not

 nam Is Char a Control?
 ttl Assembler Library Module


 psect IS_CNTRL,0,0,0,0,0


IS_CNTRL:
 cmpb #$7f
 bhs yes
 cmpb #$1f
 bhi exit not control, zero cleared

yes
 orcc #%00000100 set zero

exit
 rts

 endsect