diff --git a/blk/818 b/blk/818
index 983c641..704b139 100644
--- a/blk/818
+++ b/blk/818
@@ -2,4 +2,4 @@
         DI 3 SUBxi, AX [DI] MOVx[], ( prev )
         AX AX ORxx,
     JNZ, AGAIN, ( loop )
-    AX INCx, ( NZ ) RETn,
+    SI DECx, ( start of string, and NZ ) RETn,
diff --git a/recipes/pcat/xcomp.fs b/recipes/pcat/xcomp.fs
index a9032d8..b68ed68 100644
--- a/recipes/pcat/xcomp.fs
+++ b/recipes/pcat/xcomp.fs
@@ -9,7 +9,8 @@ RS_ADDR 0x80 - CONSTANT RAMSTART
 CODE (emit)
     AX POPx, AH 0x0e MOVri, ( print char ) 0x10 INT,
 ;CODE
-CODE (key) AH AH XORrr, 0x16 INT, AX PUSHx, ;CODE
+CODE (key)
+    AH AH XORrr, 0x16 INT, AH AH XORrr, AX PUSHx, ;CODE
 380 LOAD  ( xcomp core high )
 (entry) _
 ( Update LATEST )