Add a "custom" mode with the intent that software will poke around in the

vidparam structure itself.

src/conio/ciolib.h

@@ -34,6 +34,7 @@
 #ifndef _CIOLIB_H_
 #define _CIOLIB_H_
 
+#include <limits.h>	/* INT_MAX */
 #include <string.h>	/* size_t */
 #include "gen_defs.h"
 
@@ -202,6 +203,9 @@ enum text_modes
 	VESA_132X43	= 213,
 	VESA_132X50	= 206,
 	VESA_132X60	= 196,
+
+	/* Custom Mode */
+	CIOLIB_MODE_CUSTOM = INT_MAX,
 };
 
 #define COLOR_MODE	C80

src/conio/vidmodes.c

@@ -112,6 +112,8 @@ struct video_params vparams[] = {
 	/* Awesome modes */
 	{ST132X37_16_9, COLOUR_PALETTE, 132, 37, 14, 15, 16, 8, 1},
 	{ST132X52_5_4, COLOUR_PALETTE, 132, 52, 14, 15, 16, 8, 1},
+	/* Custom mode */
+	{CIOLIB_MODE_CUSTOM, COLOUR_PALETTE, 80, 25, 14, 15, 16, 8, 1},
 };
 
 uint32_t palettes[5][16] = {

src/conio/vidmodes.h

@@ -107,7 +107,7 @@ enum {
 	,ATARI_PALETTE
 };
 
-extern struct video_params vparams[52];
+extern struct video_params vparams[53];
 #define NUMMODES      (sizeof(vparams) / sizeof(struct video_params))
 extern uint32_t palettes[5][16];
 extern struct dac_colors dac_default[TOTAL_DAC_SIZE];