source: buchla-68k/include/vsdd.h

/*
   =============================================================================
        vsdd.h -- header for Matra-Harris 82716 VSDD video display functions
        Version 10 -- 1987-05-27 -- D.N. Lynx Crowe
        (c) Copyright 1987 -- D.N. Lynx Crowe
   =============================================================================
*/

#pragma once

#include "stdint.h"

#define VSDD    ((uint16_t *)0x200000)

#define V_CHITE 12u             /* Character height */

/* object descriptor flags */

#define V_CBS   0x0800u         /* 0 = Bit Map, 1 = Character */
#define V_RES0  0x0000u         /* Resolution 0: char 16, bit - */
#define V_RES1  0x0200u         /* Resolution 1: char  6, bit - */
#define V_RES2  0x0400u         /* Resolution 2: char  8, bit 2 */
#define V_RES3  0x0600u         /* Resolution 3: char 12, bit 4 */
#define V_CRS   0x0100u         /* Conceal/Reveal Select */

#define V_PSE   0x0080u         /* Proportional space enable */
#define V_FAD   0x0040u         /* Full attributes select */
#define V_OBL   0x0020u         /* Object blink */
#define V_BLA   0x0010u         /* Object blank */

#define V_HCR   0x0008u         /* High color resolution */
#define V_TDE   0x0004u         /* Transparency detect enable */
#define V_DCS0  0x0000u         /* Default color select 0 */
#define V_DCS1  0x0001u         /* Default color select 1 */
#define V_DCS2  0x0002u         /* Default color select 2 */
#define V_DCS3  0x0003u         /* Default color select 3 */

/* Preset flags for bitmap and character objects */

#define V_BTYPE 0u
#define V_CTYPE (V_CBS | V_RES2 | ((V_CHITE - 1) << 12))

/* character attribute flags */

#define C_ALTCS 0x8000u
#define C_TFGND 0x4000u
#define C_TBGND 0x2000u
#define C_WIDE  0x1000u

#define C_MASK  0x0800u
#define C_INVRT 0x0400u
#define C_BLINK 0x0200u
#define C_ULINE 0x0100u

struct octent {                 /* Object control table entry */

        int16_t         ysize,  /* Height of object in pixels */
                        xsize;  /* Width of object in pixels */

        int16_t         objx,   /* Object x location */
                        objy;   /* Object y location */

        volatile        uint16_t        *obase; /* Base of object data */

        int8_t          opri,   /* Current object priority */
                        obank;  /* Object bank 0..3 */

        uint16_t        odtw0,  /* Object descriptor table word 0 */
                        odtw1;  /* Object descriptor table word 1 */
};