Subversion Repositories Shiroi

/* $Id: video.c 19 2024-08-29 07:16:04Z nishi $ */

#include "video.h"

#include "math.h"

#include "../char.h"
#include "../io.h"

int scrwidth;
int scrheight;

short vdp_addr;
short vdp_data;
short vdg_addr;
short vdg_data;

void write_vram(unsigned short addr){
        if(vdp_addr != -1){
                addr |= 0x4000;
                outp(vdp_addr, addr & 0x00ff);
                outp(vdp_addr, ((addr & 0xff00) >> 8));
        }
#ifndef ONLY_VDP        
        else if(vdg_addr != -1){
                outp(vdg_addr, addr & 0x00ff);
                outp(vdg_addr, ((addr & 0xff00) >> 8));
        }
#endif
}

void read_vram(unsigned short addr){
        if(vdp_addr != -1){
                outp(vdp_addr, addr & 0x00ff);
                outp(vdp_addr, ((addr & 0xff00) >> 8));
        }
#ifndef ONLY_VDP
        else if(vdg_addr != -1){
                outp(vdg_addr, addr & 0x00ff);
                outp(vdg_addr, ((addr & 0xff00) >> 8));
        }
#endif
}

void setvramaddr(unsigned short addr){
        if(vdp_addr != -1){
                write_vram(0x800 + addr);
        }
#ifndef ONLY_VDP
        else if(vdg_addr != -1){
                write_vram(addr);
        }
#endif
}

void setreadvramaddr(unsigned short addr){
        if(vdp_addr != -1){
                read_vram(0x800 + addr);
        }
#ifndef ONLY_VDP
        else if(vdg_addr != -1){
                read_vram(addr);
        }
#endif
}

void vramchar(unsigned char c){
        if(vdp_addr != -1){
                outp(vdp_data, c - 0x20);
        }
#ifndef ONLY_VDP
        else if(vdg_addr != -1){
                if(c == 248){
                        outp(vdg_data, 0);
                }else{
                        outp(vdg_data, toupper(c) - 'A' + 1);
                }
        }
#endif
}

void _vramchar(unsigned char c){
        if(vdp_addr != -1){
                outp(vdp_data, c);
        }
#ifndef ONLY_VDP
        else if(vdg_addr != -1){
                outp(vdg_data, c);
        }
#endif
}

unsigned char getvramchar(void){
        if(vdp_addr != -1){
                return inp(vdp_data) + 0x20;
        }
#ifndef ONLY_VDP
        else if(vdg_addr != -1){
                return inp(vdg_data) - 1 + 'A';
        }
#endif
        return 0;
}

void scroll_y(void){
        int i;
        int size = muli(scrwidth, scrheight - 1);
        for(i = 0; i < size; i++){
                setreadvramaddr(i + scrwidth);
                unsigned char ch = getvramchar();
                setvramaddr(i);
                vramchar(ch);
        }
        for(i = 0; i < scrwidth; i++){
                vramchar(' ');
        }
}

void video_init(void){
        int i;
        if(vdp_addr != -1){
                scrwidth = 32;
                scrheight = 24;

                outp(vdp_addr, 0x00);
                outp(vdp_addr, 0x80);
        
                outp(vdp_addr, 0xd8);
                outp(vdp_addr, 0x81);
        
                outp(vdp_addr, 0x02);
                outp(vdp_addr, 0x82);
        
                outp(vdp_addr, 0x50);
                outp(vdp_addr, 0x83);
        
                outp(vdp_addr, 0x00);
                outp(vdp_addr, 0x84);
        
                outp(vdp_addr, 0x29);
                outp(vdp_addr, 0x85);
        
                outp(vdp_addr, 0x03);
                outp(vdp_addr, 0x86);
        
                outp(vdp_addr, 0xe4);
                outp(vdp_addr, 0x87);
                
                /*
                 * VDP:
                 * 0x0000-0x0800: font
                 * 0x0800-0x1400: pattern
                 * 0x1400-0x1480: color
                 * 0x1480-0x1500: sprite attr
                 * 0x1800-0x2000: sprite pattern
                 */
        
                write_vram(0);
                for(i = 0; i < 0x800; i++) outp(vdp_data, *((unsigned char*)(0x6000 - 2048 + i)));
        
                write_vram(0x1400);
                for(i = 0; i < 0x20; i++) outp(vdp_data, 0xf0);
                write_vram(0x1400 + 0x10);
                for(i = 0; i < 0x10; i++) outp(vdp_data, ((i & 0xf) << 4) | 0);
        }
#ifndef ONLY_VDP
        else if(vdg_addr != -1){
                scrwidth = 32;
                scrheight = 16;
        }
#endif
}

void video_card(int t, int port){
        if(t == 0x01){
                vdp_addr = port - 2;
                vdp_data = port - 1;
        }else if(t == 0x02){
                vdg_addr = port - 2;
                vdg_data = port - 1;
        }
}