diff --git a/src/asm/parser.y b/src/asm/parser.y
index 35e052d7..9ce3af9c 100644
--- a/src/asm/parser.y
+++ b/src/asm/parser.y
@@ -89,7 +89,7 @@
 	enum { REG_BC_IND, REG_DE_IND, REG_HL_INDINC, REG_HL_INDDEC };
 
 	// LD/INC/ADD/DEC allow SP, PUSH/POP allow AF
-	enum { REG_BC, REG_DE, REG_HL, REG_SP, REG_AF };
+	enum { REG_BC = 0, REG_DE = 1, REG_HL = 2, REG_SP = 3, REG_AF = 3 };
 
 	// CC_NZ == CC_Z ^ 1, and CC_NC == CC_C ^ 1
 	enum { CC_NZ, CC_Z, CC_NC, CC_C };