New function videomode() for the C128. Marked toggle_videomode as deprecated.

git-svn-id: svn://svn.cc65.org/cc65/trunk@4126 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/c128/videomode.s

@@ -0,0 +1,33 @@
+;
+; Ullrich von Bassewitz, 2009-09-07
+;
+; unsigned char __fastcall__ videomode (unsigned char Mode);
+; /* Set the video mode, return the old mode */
+;
+
+	.export		_videomode
+        .import         SWAPPER, BSOUT  
+
+        .include        "c128.inc"
+
+
+.proc   _videomode
+
+        cmp     MODE                    ; Do we have this mode already?
+        beq     @L9
+
+        lda     MODE                    ; Get current mode ...
+        pha                             ; ... and save it
+
+        jsr     SWAPPER                 ; Toggle the mode
+ 	lda     #14
+       	jsr     BSOUT                   ; Switch to lower case chars
+        pla                             ; Get old mode into A
+
+; Done, old mode is in A
+
+@L9:    ldx     #$00                    ; Clear high byte
+        rts
+
+.endproc
+