video.h
#include#define begin { #define end } char screen[1600]; //NOTE that v1 to v8 and i must be in registers! register char v1 @4; register char v2 @5; register char v3 @6; register char v4 @7; register char v5 @8; register char v6 @9; register char v7 @10; register char v8 @11; register int i @12; flash char pos[8]={0x80,0x40,0x20,0x10,0x08,0x04,0x02,0x01}; //define some character bitmaps //5x7 characters flash char bitmap[39][7]={ //0 0b01110000, 0b10001000, 0b10011000, 0b10101000, 0b11001000, 0b10001000, 0b01110000, //1 0b00100000, 0b01100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b01110000, //2 0b01110000, 0b10001000, 0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b11111000, //3 0b11111000, 0b00010000, 0b00100000, 0b00010000, 0b00001000, 0b10001000, 0b01110000, //4 0b00010000, 0b00110000, 0b01010000, 0b10010000, 0b11111000, 0b00010000, 0b00010000, //5 0b11111000, 0b10000000, 0b11110000, 0b00001000, 0b00001000, 0b10001000, 0b01110000, //6 0b01000000, 0b10000000, 0b10000000, 0b11110000, 0b10001000, 0b10001000, 0b01110000, //7 0b11111000, 0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b10000000, 0b10000000, //8 0b01110000, 0b10001000, 0b10001000, 0b01110000, 0b10001000, 0b10001000, 0b01110000, //9 0b01110000, 0b10001000, 0b10001000, 0b01111000, 0b00001000, 0b00001000, 0b00010000, //A 0b01110000, 0b10001000, 0b10001000, 0b10001000, 0b11111000, 0b10001000, 0b10001000, //B 0b11110000, 0b10001000, 0b10001000, 0b11110000, 0b10001000, 0b10001000, 0b11110000, //C 0b01110000, 0b10001000, 0b10000000, 0b10000000, 0b10000000, 0b10001000, 0b01110000, //D 0b11110000, 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b11110000, //E 0b11111000, 0b10000000, 0b10000000, 0b11111000, 0b10000000, 0b10000000, 0b11111000, //F 0b11111000, 0b10000000, 0b10000000, 0b11111000, 0b10000000, 0b10000000, 0b10000000, //G 0b01110000, 0b10001000, 0b10000000, 0b10011000, 0b10001000, 0b10001000, 0b01110000, //H 0b10001000, 0b10001000, 0b10001000, 0b11111000, 0b10001000, 0b10001000, 0b10001000, //I 0b01110000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b01110000, //J 0b00111000, 0b00010000, 0b00010000, 0b00010000, 0b00010000, 0b10010000, 0b01100000, //K 0b10001000, 0b10010000, 0b10100000, 0b11000000, 0b10100000, 0b10010000, 0b10001000, //L 0b10000000, 0b10000000, 0b10000000, 0b10000000, 0b10000000, 0b10000000, 0b11111000, //M 0b10001000, 0b11011000, 0b10101000, 0b10101000, 0b10001000, 0b10001000, 0b10001000, //N 0b10001000, 0b10001000, 0b11001000, 0b10101000, 0b10011000, 0b10001000, 0b10001000, //O 0b01110000, 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b01110000, //P 0b11110000, 0b10001000, 0b10001000, 0b11110000, 0b10000000, 0b10000000, 0b10000000, //Q 0b01110000, 0b10001000, 0b10001000, 0b10001000, 0b10101000, 0b10010000, 0b01101000, //R 0b11110000, 0b10001000, 0b10001000, 0b11110000, 0b10100000, 0b10010000, 0b10001000, //S 0b01111000, 0b10000000, 0b10000000, 0b01110000, 0b00001000, 0b00001000, 0b11110000, //T 0b11111000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, //U 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b01110000, //V 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b01010000, 0b00100000, //W 0b10001000, 0b10001000, 0b10001000, 0b10101000, 0b10101000, 0b10101000, 0b01010000, //X 0b10001000, 0b10001000, 0b01010000, 0b00100000, 0b01010000, 0b10001000, 0b10001000, //Y 0b10001000, 0b10001000, 0b10001000, 0b01010000, 0b00100000, 0b00100000, 0b00100000, //Z 0b11111000, 0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b10000000, 0b11111000, //. 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00111000, 0b00111000, //blank 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //figure2 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000 }; //================================ //3x5 font numbers, then letters //packed two per definition for fast //copy to the screen at x-position divisible by 4 flash char smallbitmap[39][5]={ //0 0b11101110, 0b10101010, 0b10101010, 0b10101010, 0b11101110, //1 0b01000100, 0b11001100, 0b01000100, 0b01000100, 0b11101110, //2 0b11101110, 0b00100010, 0b11101110, 0b10001000, 0b11101110, //3 0b11101110, 0b00100010, 0b11101110, 0b00100010, 0b11101110, //4 0b10101010, 0b10101010, 0b11101110, 0b00100010, 0b00100010, //5 0b11101110, 0b10001000, 0b11101110, 0b00100010, 0b11101110, //6 0b11001100, 0b10001000, 0b11101110, 0b10101010, 0b11101110, //7 0b11101110, 0b00100010, 0b01000100, 0b10001000, 0b10001000, //8 0b11101110, 0b10101010, 0b11101110, 0b10101010, 0b11101110, //9 0b11101110, 0b10101010, 0b11101110, 0b00100010, 0b01100110, //: 0b00000000, 0b01000100, 0b00000000, 0b01000100, 0b00000000, //= 0b00000000, 0b11101110, 0b00000000, 0b11101110, 0b00000000, //blank 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //A 0b11101110, 0b10101010, 0b11101110, 0b10101010, 0b10101010, //B 0b11001100, 0b10101010, 0b11101110, 0b10101010, 0b11001100, //C 0b11101110, 0b10001000, 0b10001000, 0b10001000, 0b11101110, //D 0b11001100, 0b10101010, 0b10101010, 0b10101010, 0b11001100, //E 0b11101110, 0b10001000, 0b11101110, 0b10001000, 0b11101110, //F 0b11101110, 0b10001000, 0b11101110, 0b10001000, 0b10001000, //G 0b11101110, 0b10001000, 0b10001000, 0b10101010, 0b11101110, //H 0b10101010, 0b10101010, 0b11101110, 0b10101010, 0b10101010, //I 0b11101110, 0b01000100, 0b01000100, 0b01000100, 0b11101110, //J 0b00100010, 0b00100010, 0b00100010, 0b10101010, 0b11101110, //K 0b10001000, 0b10101010, 0b11001100, 0b11001100, 0b10101010, //L 0b10001000, 0b10001000, 0b10001000, 0b10001000, 0b11101110, //M 0b10101010, 0b11101110, 0b11101110, 0b10101010, 0b10101010, //N 0b00000000, 0b11001100, 0b10101010, 0b10101010, 0b10101010, //O 0b01000100, 0b10101010, 0b10101010, 0b10101010, 0b01000100, //P 0b11101110, 0b10101010, 0b11101110, 0b10001000, 0b10001000, //Q 0b01000100, 0b10101010, 0b10101010, 0b11101110, 0b01100110, //R 0b11101110, 0b10101010, 0b11001100, 0b11101110, 0b10101010, //S 0b11101110, 0b10001000, 0b11101110, 0b00100010, 0b11101110, //T 0b11101110, 0b01000100, 0b01000100, 0b01000100, 0b01000100, //U 0b10101010, 0b10101010, 0b10101010, 0b10101010, 0b11101110, //V 0b10101010, 0b10101010, 0b10101010, 0b10101010, 0b01000100, //W 0b10101010, 0b10101010, 0b11101110, 0b11101110, 0b10101010, //X 0b00000000, 0b10101010, 0b01000100, 0b01000100, 0b10101010, //Y 0b10101010, 0b10101010, 0b01000100, 0b01000100, 0b01000100, //Z 0b11101110, 0b00100010, 0b01000100, 0b10001000, 0b11101110 }; //================================== //plot one point //at x,y with color 1=white 0=black 2=invert #pragma warn- void video_pt(char x, char y, char c) begin #asm ; i=(x>>3) + ((int)y<<4) ; the byte with the pixel in it push r16 ldd r30,y+2 ;get x lsr r30 lsr r30 lsr r30 ;divide x by 8 ldd r12,y+1 ;get y lsl r12 ;mult y by 16 clr r13 lsl r12 rol r13 lsl r12 rol r13 lsl r12 rol r13 add r12, r30 ;add in x/8 ;v2 = screen[i]; r5 ;v3 = pos[x & 7]; r6 ;v4 = c r7 ldi r30,low(_screen) ldi r31,high(_screen) add r30, r12 adc r31, r13 ld r5,Z ;get screen byte ldd r26,y+2 ;get x ldi r27,0 andi r26,0x07 ;form x & 7 ldi r30,low(_pos*2) ldi r31,high(_pos*2) add r30,r26 adc r31,r27 lpm r6,Z ld r16,y ;get c ;if (v4==1) screen[i] = v2 | v3 ; ;if (v4==0) screen[i] = v2 & ~v3; ;if (v4==2) screen[i] = v2 ^ v3 ; cpi r16,1 brne tst0 or r5,r6 tst0: cpi r16,0 brne tst2 com r6 and r5,r6 tst2: cpi r16,2 brne writescrn eor r5,r6 writescrn: ldi r30,low(_screen) ldi r31,high(_screen) add r30, r12 adc r31, r13 st Z, r5 ;write the byte back to the screen pop r16 #endasm end #pragma warn+ //================================== // put a big character on the screen // c is index into bitmap void video_putchar(char x, char y, char c) begin v7 = x; for (v6=0;v6<7;v6++) begin v1 = bitmap[c][v6]; v8 = y+v6; video_pt(v7, v8, (v1 & 0x80)==0x80); video_pt(v7+1, v8, (v1 & 0x40)==0x40); video_pt(v7+2, v8, (v1 & 0x20)==0x20); video_pt(v7+3, v8, (v1 & 0x10)==0x10); video_pt(v7+4, v8, (v1 & 0x08)==0x08); end end //================================== // put a string of big characters on the screen void video_puts(char x, char y, char *str) begin char i ; for (i=0; str[i]!=0; i++) begin if (str[i]>=0x30 && str[i]<=0x3a) video_putchar(x,y,str[i]-0x30); else if (str[i]==0x2E) video_putchar(x,y,36); else video_putchar(x,y,str[i]-0x40+9); x = x+6; end end //================================== // put a small character on the screen // x-cood must be on divisible by 4 // c is index into bitmap void video_smallchar(char x, char y, char c) begin char mask; i=((int)x>>3) + ((int)y<<4) ; if (x == (x & 0xf8)) mask = 0x0f; //f8 else mask = 0xf0; screen[i] = (screen[i] & mask) | (smallbitmap[c][0] & ~mask); screen[i+16] = (screen[i+16] & mask) | (smallbitmap[c][1] & ~mask); screen[i+32] = (screen[i+32] & mask) | (smallbitmap[c][2] & ~mask); screen[i+48] = (screen[i+48] & mask) | (smallbitmap[c][3] & ~mask); screen[i+64] = (screen[i+64] & mask) | (smallbitmap[c][4] & ~mask); end //================================== // put a string of small characters on the screen // x-cood must be on divisible by 4 void video_putsmalls(char x, char y, char *str) begin char i ; for (i=0; str[i]!=0; i++) begin if (str[i]>=0x30 && str[i]<=0x3a) video_smallchar(x,y,str[i]-0x30); else video_smallchar(x,y,str[i]-0x40+12); x = x+4; end end //================================== //plot a line //at x1,y1 to x2,y2 with color 1=white 0=black 2=invert //NOTE: this function requires signed chars //Code is from David Rodgers, //"Procedural Elements of Computer Graphics",1985 void video_line(char x1, char y1, char x2, char y2, char c) begin int e; signed char dx,dy,j, temp; signed char s1,s2, xchange; signed char x,y; x = x1; y = y1; dx = cabs(x2-x1); dy = cabs(y2-y1); s1 = csign(x2-x1); s2 = csign(y2-y1); xchange = 0; if (dy>dx) begin temp = dx; dx = dy; dy = temp; xchange = 1; end e = ((int)dy<<1) - dx; for (j=0; j<=dx; j++) begin video_pt(x,y,c) ; if (e>=0) begin if (xchange==1) x = x + s1; else y = y + s2; e = e - ((int)dx<<1); end if (xchange==1) y = y + s2; else x = x + s1; e = e + ((int)dy<<1); end end //================================== //return the value of one point //at x,y with color 1=white 0=black 2=invert char video_set(char x, char y) begin //The following construction //detects exactly one bit at the x,y location i=((int)x>>3) + ((int)y<<4) ; return ( screen[i] & 1<<(7-(x & 0x7))); end