diff --git a/blk/056 b/blk/056
index d3db076..5e28f9b 100644
--- a/blk/056
+++ b/blk/056
@@ -6,7 +6,9 @@ Logic
 ><   n l h -- f Push true if l < n < h
 =><= n l h -- f Push true if l <= n <= h
 CMP  n1 n2 -- n Compare n1 and n2 and set n to -1, 0, or 1.
-               n=0: a1=a2. n=1: a1>a2. n=-1: a1<a2.
+                n=0: a1=a2. n=1: a1>a2. n=-1: a1<a2.
+MIN  a b -- n   Returns the lowest of a and b
+MAX  a b -- n   Returns the highest of a and b
 NOT  f -- f     Push the logical opposite of f
 
 
diff --git a/blk/081 b/blk/081
index c894fc6..e216810 100644
--- a/blk/081
+++ b/blk/081
@@ -1,6 +1,6 @@
 RAMSTART  FUTURE USES          +3c       BLK(*
-+02       CURRENT              +3e       FUTURE USES
-+04       HERE                 
++02       CURRENT              +3e       XYPOS
++04       HERE                 +40       FUTURE USES
 +06       C<?                  +51       CURRENTPTR
 +08       C<* override         +53       (emit) override
 +0a       NLPTR                +55       (key) override
diff --git a/blk/083 b/blk/083
index a45d747..a3afc08 100644
--- a/blk/083
+++ b/blk/083
@@ -7,8 +7,8 @@ WORDBUF is the buffer used by WORD
 BOOT C< PTR is used when Forth boots from in-memory
 source. See "Initialization sequence" below.
 
-
-
+XYPOS Current position of the cursor on screen. The meaning of
+the pos in terms of row and cols is driver-dependent.
 
 
 
diff --git a/blk/393 b/blk/393
index e602432..d4092d0 100644
--- a/blk/393
+++ b/blk/393
@@ -3,6 +3,7 @@
 : HERE 0x04 RAM+ ;
 : CURRENT* 0x51 RAM+ ;
 : CURRENT CURRENT* @ ;
+: XYPOS 0x40 RAM+ ;
 
 ( w -- a f )
 : (find) CURRENT @ SWAP _find ;
diff --git a/blk/394 b/blk/394
index d6742b5..36de94d 100644
--- a/blk/394
+++ b/blk/394
@@ -2,14 +2,11 @@
 : ERR LIT< (print) (find) IF EXECUTE THEN ABORT ;
 : = CMP NOT ; : < CMP -1 = ; : > CMP 1 = ;
 : 0< 32767 > ; : >= < NOT ; : <= > NOT ; : 0>= 0< NOT ;
-( n l h -- f )
-: >< 2 PICK > ( n l f ) ROT ROT > AND ;
+: >< ( n l h -- f ) 2 PICK > ( n l f ) ROT ROT > AND ;
 : =><= 2 PICK >= ( n l f ) ROT ROT >= AND ;
-( a -- a+1 c )
-: C@+ DUP C@ SWAP 1+ SWAP ;
-( c a -- a+1 )
-: C!+ SWAP OVER C! 1+ ;
-( a -- a-1 c )
-: C@- DUP C@ SWAP 1- SWAP ;
-( c a -- a-1 )
-: C!- SWAP OVER C! 1- ;
+: MIN ( n n - n ) 2DUP > IF SWAP THEN DROP ;
+: MAX ( n n - n ) 2DUP < IF SWAP THEN DROP ;
+: C@+ ( a -- a+1 c ) DUP C@ SWAP 1+ SWAP ;
+: C!+ ( c a -- a+1 ) SWAP OVER C! 1+ ;
+: C@- ( a -- a-1 c ) DUP C@ SWAP 1- SWAP ;
+: C!- ( c a -- a-1 ) SWAP OVER C! 1- ;
diff --git a/blk/627 b/blk/627
index 4aa6757..b8ded29 100644
--- a/blk/627
+++ b/blk/627
@@ -1,14 +1,6 @@
-: _set ( row col tilenum -- )
-    ROT 5 LSHIFT ROT OR 0x7800 OR _ctl
-    _data 1 _zero
+: (emit)
+    XYPOS @ 2 * 0x7800 OR _ctl
+    0x20 - 0x5e MIN ( tilenum ) _data 1 _zero
+    XYPOS @ 1+ DUP [ VDP_COLS VDP_ROWS * LITN ]
+    = IF DROP 0 THEN XYPOS !
 ;
-: VDP$
-    9 0 DO _idat I 2 * + @ _ctl LOOP _blank
-    ( palettes )
-    0xc000 _ctl
-    ( BG ) 1 _zero 0x3f _data 14 _zero
-    ( sprite, inverted colors ) 0x3f _data 15 _zero
-    0x4000 _ctl 0x5e 0 DO ~FNT I 7 * + _sfont LOOP
-    0 0 1 _set
-;
-
diff --git a/blk/628 b/blk/628
new file mode 100644
index 0000000..abd4ef2
--- /dev/null
+++ b/blk/628
@@ -0,0 +1,9 @@
+: VDP$
+    9 0 DO _idat I 2 * + @ _ctl LOOP _blank
+    ( palettes )
+    0xc000 _ctl
+    ( BG ) 1 _zero 0x3f _data 14 _zero
+    ( sprite, inverted colors ) 0x3f _data 15 _zero
+    0x4000 _ctl 0x5e 0 DO ~FNT I 7 * + _sfont LOOP
+    0 XYPOS !
+;
diff --git a/emul/forth.bin b/emul/forth.bin
index 85666f4..4bf769f 100644
Binary files a/emul/forth.bin and b/emul/forth.bin differ
diff --git a/recipes/sms/xcomp.fs b/recipes/sms/xcomp.fs
index 8fe4c50..9353fe6 100644
--- a/recipes/sms/xcomp.fs
+++ b/recipes/sms/xcomp.fs
@@ -21,12 +21,12 @@ CURRENT @ XCURRENT !
 282 LOAD  ( boot.z80 )
 393 LOAD  ( xcomp core low )
 CREATE ~FNT CPFNT7x7
-623 627 LOADR ( VDP )
-: (key) 0 ; : (emit) DROP ;
+623 628 LOADR ( VDP )
+: (key) 4 ;
 420 LOAD  ( xcomp core high )
 (entry) _
 ( Update LATEST )
 PC ORG @ 8 + !
-," VDP$ BYE "
+," VDP$ " EOT,
 ORG @ 0x100 - 256 /MOD 2 PC! 2 PC!
 H@ 256 /MOD 2 PC! 2 PC!