diff --git a/README.md b/README.md
index d16f9dc..ee35994 100644
--- a/README.md
+++ b/README.md
@@ -5,15 +5,14 @@
 A fig-FORTH<sup>2</sup> implementation for the Z80 that can be built using TASM<sup>3</sup>:
    
 ```
-$ tasm -80 -b figforth.z80 forth.com forth.lst
+$ tasm -80 -b figforth.asm forth.com forth.lst
 ```
 
 The resulting `forth.com` executable can be run in CP/M. For example<sup>4</sup>:
 ```
 A>FORTH
 
-No file
-Z80 fig-FORTH 1.3a
+Z80 fig-FORTH 1.3b
 : CUBE ( N -> N.  CUBE A NUMBER ) 
    DUP DUP  ( NOW THERE ARE THREE COPIES ) 
    * * 
diff --git a/discio.asm b/discio.asm
index dd41bc4..589c5c5 100644
--- a/discio.asm
+++ b/discio.asm
@@ -325,10 +325,13 @@ FILE:	.WORD	DOCOL			; The file type is determined by FTYPE.
 	.WORD	FCB
 	.WORD	LIT,OPNFIL		; open file
 	.WORD	BDOS
-	.WORD	LIT,0FFH		; check no error
+	.WORD	LIT,0FFH		; check for error
 	.WORD	EQUAL
+	.WORD	DUP
+	.WORD	ZEQU
+	.WORD	WARN,STORE		; set WARNING variable
 	.WORD	LIT,8
-	.WORD	QERR
+	.WORD	QERR	
 	.WORD	SEMIS
 ;
 	.BYTE	84H		;LOAD