diff --git a/src/altair8800/test.asm b/src/altair8800/test.asm
index 927c848..6c45320 100644
--- a/src/altair8800/test.asm
+++ b/src/altair8800/test.asm
@@ -37,7 +37,7 @@ run:
 	jnc	run
 	in	0ffh
 	mov	d, a
-	CPI	0
+	cpi	0
 	jz	print
 	jmp	run