diff --git a/FORTH.ASM b/FORTH.ASM
index 6ec3fcd..5dd77a7 100644
--- a/FORTH.ASM
+++ b/FORTH.ASM
@@ -107,11 +107,11 @@
 	%ENDMACRO
 
 
-	%MACRO DEFCONST 3
+	%MACRO DEFCONST 2
 	DEFWORD_RAW %1, %2
-	PUSH CONST_%1
+	PUSH WORD [CONST_%1]
 	NEXT
-	CONST_%1 EQU %3
+CONST_%1:
 	%ENDMACRO
 
 
@@ -135,8 +135,9 @@
 _START:
 	;; Progran begins
 	MOV BP, SP
-	SUB BP, 1024				; why can't I use SP as a base for
-								; load effective address?
+	SUB BP, 1024
+	MOV WORD [CONST_SP_INITIAL], SP
+
 	MOV SI, INDIRECT_START
 	NEXT
 
@@ -192,8 +193,7 @@
 	JMP DOT_INT
 	
 
-	;; TODO: should not be immediate, that's just for debugging
-	DEFWORD_RAW_IMMEDIATE BYE, 'BYE'
+	DEFWORD_RAW BYE, 'BYE'
 	FLUSH
 	QUIT_PROC
 
@@ -241,6 +241,23 @@
 	NEXT
 
 
+	DEFWORD_RAW SLASHMOD, '/MOD'
+	POP DX
+	POP AX
+	IDIV DX
+	PUSH DX						; Remainder
+	PUSH AX						; Quotient
+	NEXT
+
+
+	DEFWORD_RAW _TIMES, '*'
+	POP AX
+	POP DX
+	IMUL DX
+	PUSH AX
+	NEXT
+
+
 	DEFWORD_RAW AND, 'AND'
 	POP AX
 	POP DX
@@ -287,6 +304,41 @@
 	PUSH BX
 	PUSH AX
 	NEXT
+
+
+	DEFWORD_RAW TEST_WRITE_FILE, 'TEST-WRITE-FILE'
+	MOV AL, F_WRITE
+	MOV DX, DUMP
+	OPENF
+	JC .OPEN
+
+	MOV BX, AX					; Handle
+	MOV CX, 4
+	MOV DX, DUMP
+	WRITEF
+	JC .WRITE
+
+	CLOSEF
+	JC .CLOSE
+
+	NEXT
+
+.OPEN:
+	MOV DX, MSG_OPENF_FAILED
+	WRITESOUT
+	NEXT
+
+.WRITE:
+	;; 06h - invalid handle
+	PUSH AX
+	MOV DX, MSG_WRITEF_FAILED
+	WRITESOUT
+	NEXT
+
+.CLOSE:
+	MOV DX, MSG_CLOSEF_FAILED
+	WRITESOUT
+	NEXT
 	
 
 	%INCLUDE "IOWORDS.ASM"
@@ -300,6 +352,10 @@
 	DEFVAR HERE, 'HERE'
 	DW HERE_START
 
+
+	DEFCONST SP_INITIAL, 'S0'
+	DW 0
+
 	
 	;; LATEST must be the last word defined in FORTH.ASM!
 	DEFVAR LATEST, 'LATEST'
@@ -308,6 +364,11 @@
 
 ;;; PROGRAM DATA ;;;
 	MSG DB 'DOS FORTH', 0Dh, 0Ah, '$'
+	DUMP DB 'DUMP.COM', 0
+	DUMP_LEN EQU 8
+
+	MSG_CLOSEF_FAILED DB 'CLOSEF FAILED', 0Dh, 0Ah, '$'
+	MSG_WRITEF_FAILED DB 'WRITEF FAILED', 0Dh, 0Ah, '$'
 
 
 	ALIGN 4