X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=libsrc%2Fcommon%2Fisgraph.s;h=e2073aea2274b641babb487589503c812872ff75;hb=a63d35278cbfa7d3b1df34d2fb329e758e8cddc4;hp=91f482c5664d4fe91cc4c594d513cd729fab4e4a;hpb=53dd513176425872128ef26031d00952ef7a0628;p=cc65

diff --git a/libsrc/common/isgraph.s b/libsrc/common/isgraph.s
index 91f482c56..e2073aea2 100644
--- a/libsrc/common/isgraph.s
+++ b/libsrc/common/isgraph.s
@@ -8,9 +8,15 @@
 	.import		__ctype
 
 _isgraph:
+	cpx	#$00		; Char range ok?
+	bne	@L1		; Jump if no
 	tay
 	lda	__ctype,y	; Get character classification
 	eor	#$30		; NOT control and NOT space
 	and 	#$30   	       	; Mask character bits
 	rts
 
+@L1:	lda	#$00		; Return false
+	tax
+	rts
+