diff --git a/libsrc/runtime/popa.s b/libsrc/runtime/popa.s
index 6c7c9308b..37bbc7b68 100644
--- a/libsrc/runtime/popa.s
+++ b/libsrc/runtime/popa.s
@@ -9,12 +9,18 @@
 
 .proc	popa
 
+.ifpc02
+	lda	(sp)
+.else
 	ldy 	#0
  	lda	(sp),y		; Read byte
-	inc	sp
-	bne	@L1
-	inc	sp+1
-@L1:	rts
+.endif
+      	inc	sp
+       	beq	@L1
+	rts
+
+@L1:	inc	sp+1
+	rts
 
 .endproc