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diff --git a/16/xw/mxsl.asm b/16/xw/mxsl.asm
new file mode 100755
index 00000000..d7908855
--- /dev/null
+++ b/16/xw/mxsl.asm
@@ -0,0 +1,62 @@
+;-----------------------------------------------------------
+;
+; MXLN.ASM - Start line function
+; Copyright (c) 1994 by Alessandro Scotti
+;
+;-----------------------------------------------------------
+WARN    PRO
+NOWARN  RES
+INCLUDE MODEX.DEF
+
+PUBLIC  mxStartLine
+
+MX_TEXT SEGMENT USE16 PARA PUBLIC 'CODE'
+        ASSUME cs:MX_TEXT, ds:NOTHING, es:NOTHING
+
+EXTRN   mx_BytesPerLine : WORD
+
+;-----------------------------------------------------------
+;
+; Changes the video start address to the specified line.
+;
+; Input:
+;       Line    = new start line
+; Output:
+;       none
+;
+mxStartLine     PROC FAR
+        ARG     Line:WORD       = ARG_SIZE
+        .enter  0
+        ASSUME  ds:NOTHING
+
+        mov     ax, [Line]              ; Get video offset
+        mul     [mx_BytesPerLine]
+        xchg    ax, bx                  ; Copy it into BX
+
+; Wait display
+        mov     dx, STATUS
+@@1:    in      al, dx
+        test    al, 08h
+        jnz     @@1
+
+; Set starting address
+        mov     dx, CRTC
+        mov     al, 0Ch                 ; Linear Starting Address high
+        mov     ah, bh
+        cli
+        out     dx, ax
+        mov     al, 0Dh                 ; Linear Starting Address low
+        mov     ah, bl
+        out     dx, ax
+        sti
+
+; Wait retrace
+        mov     dx, STATUS
+@@2:    in      al,dx
+        test    al, 08h
+        jz      @@2
+
+        xor     ax, ax
+        .leave  ARG_SIZE
+MX_TEXT         ENDS
+END