diff --git a/libsrc/apple2/extra/iobuf-0800.s b/libsrc/apple2/extra/iobuf-0800.s
index 02685fae7..017bc030e 100644
--- a/libsrc/apple2/extra/iobuf-0800.s
+++ b/libsrc/apple2/extra/iobuf-0800.s
@@ -70,7 +70,7 @@ iobuf_alloc:
 	ldy	#$01
 	sta	(ptr1),y
 	dey
-	lda	#$00
+	tya
 	sta	(ptr1),y
         rts