diff --git a/ASM-SYNTAX.md b/ASM-SYNTAX.md
index 5c8ff80..c9d9adf 100644
--- a/ASM-SYNTAX.md
+++ b/ASM-SYNTAX.md
@@ -43,9 +43,9 @@ instruction
 	'DIV'
 	'MUL'
 	'SWAP'
+	'PRTCHK'
 	'PRTRD'
-	'RDPRT'
-	'WRPRT'
+	'PRTWR'
 
 mov
 	'MOV' register ',' memory