// Black and white NTSC video generation with fixed point animation // D.0 is sync // D.1 is video // Mega644 version by Shane Pryor // mod by brl4@cornell.edu: // for mega1284 // for resolution 160 horizontal x 200 vertical // plays a musical scale from port B.3 // UART SPI-mode video output from Morgan D. Jones #include #include #include #include #include #include #include // optional, if preferred/// #define begin { #define end } //////////////////////////// //cycles = 63.625 * 16 Note NTSC is 63.55 //but this line duration makes each frame exactly 1/60 sec //which is nice for keeping a realtime clock // video timing #define LINE_TIME 1018 // 20 MHz 1271 #define SLEEP_TIME 999 // 20 MHz 1250 #define bytes_per_line 20 #define screen_width (bytes_per_line*8) #define screen_height 200 #define screen_array_size screen_width*screen_height/8 #define ScreenTop 30 #define ScreenBot (ScreenTop+screen_height) //sync char syncON, syncOFF; //current line number in the current frame volatile int LineCount; //160h x 160v - screen buffer and pointer char screen[screen_array_size]; int* screenindex; //One bit masks char pos[8] = {0x80,0x40,0x20,0x10,0x08,0x04,0x02,0x01}; // Musical note values // middle-C to C-above-middle-C // zeros are rests char notes[] = {150,132,117,112,100,89,79,75,0,0,0,0}; char note, musicT; //================================ //3x5 font numbers, then letters //packed two per definition for fast //copy to the screen at x-position divisible by 4 prog_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 }; //=============================================== // Full ascii 5x7 char set // Designed by: David Perez de la Cruz,and Ed Lau // see: http://instruct1.cit.cornell.edu/courses/ee476/FinalProjects/s2005/dp93/index.html prog_char ascii[128][7] = { //0 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //1 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //2 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //3 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //4 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //5 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //6 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //7 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //8 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //9 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //10 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //11 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //12 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //13 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //14 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //15 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //16 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //17 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //18 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //19 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //20 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //21 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //22 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //23 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //24 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //25 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //26 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //27 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //28 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //29 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //30 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //31 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //32 Space 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //33 Exclamation ! 0b01100000, 0b01100000, 0b01100000, 0b01100000, 0b00000000, 0b00000000, 0b01100000, //34 Quotes " 0b01010000, 0b01010000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //35 Number # 0b00000000, 0b01010000, 0b11111000, 0b01010000, 0b11111000, 0b01010000, 0b00000000, //36 Dollars $ 0b01110000, 0b10100000, 0b10100000, 0b01110000, 0b00101000, 0b00101000, 0b01110000, //37 Percent % 0b01000000, 0b10101000, 0b01010000, 0b00100000, 0b01010000, 0b10101000, 0b00010000, //38 Ampersand & 0b00100000, 0b01010000, 0b10100000, 0b01000000, 0b10101000, 0b10010000, 0b01101000, //39 Single Quote ' 0b01000000, 0b01000000, 0b01000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //40 Left Parenthesis ( 0b00010000, 0b00100000, 0b01000000, 0b01000000, 0b01000000, 0b00100000, 0b00010000, //41 Right Parenthesis ) 0b01000000, 0b00100000, 0b00010000, 0b00010000, 0b00010000, 0b00100000, 0b01000000, //42 Star * 0b00010000, 0b00111000, 0b00010000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //43 Plus + 0b00000000, 0b00100000, 0b00100000, 0b11111000, 0b00100000, 0b00100000, 0b00000000, //44 Comma , 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00010000, 0b00010000, //45 Minus - 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b11111000, 0b00000000, 0b00000000, //46 Period . 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00010000, // 47 Backslash / 0b00000000, 0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b10000000, 0b00000000, // 48 Zero 0b01110000, 0b10001000, 0b10011000, 0b10101000, 0b11001000, 0b10001000, 0b01110000, //49 One 0b00100000, 0b01100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b01110000, //50 two 0b01110000, 0b10001000, 0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b11111000, //51 Three 0b11111000, 0b00010000, 0b00100000, 0b00010000, 0b00001000, 0b10001000, 0b01110000, //52 Four 0b00010000, 0b00110000, 0b01010000, 0b10010000, 0b11111000, 0b00010000, 0b00010000, //53 Five 0b11111000, 0b10000000, 0b11110000, 0b00001000, 0b00001000, 0b10001000, 0b01110000, //54 Six 0b01000000, 0b10000000, 0b10000000, 0b11110000, 0b10001000, 0b10001000, 0b01110000, //55 Seven 0b11111000, 0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b10000000, 0b10000000, //56 Eight 0b01110000, 0b10001000, 0b10001000, 0b01110000, 0b10001000, 0b10001000, 0b01110000, //57 Nine 0b01110000, 0b10001000, 0b10001000, 0b01111000, 0b00001000, 0b00001000, 0b00010000, //58 : 0b00000000, 0b00000000, 0b00100000, 0b00000000, 0b00000000, 0b00000000, 0b00100000, //59 ; 0b00000000, 0b00000000, 0b00100000, 0b00000000, 0b00000000, 0b00100000, 0b00100000, //60 < 0b00000000, 0b00011000, 0b01100000, 0b10000000, 0b01100000, 0b00011000, 0b00000000, //61 = 0b00000000, 0b00000000, 0b01111000, 0b00000000, 0b01111000, 0b00000000, 0b00000000, //62 > 0b00000000, 0b11000000, 0b00110000, 0b00001000, 0b00110000, 0b11000000, 0b00000000, //63 ? 0b00110000, 0b01001000, 0b00010000, 0b00100000, 0b00100000, 0b00000000, 0b00100000, //64 @ 0b01110000, 0b10001000, 0b10111000, 0b10101000, 0b10010000, 0b10001000, 0b01110000, //65 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, //91 [ 0b11100000, 0b10000000, 0b10000000, 0b10000000, 0b10000000, 0b10000000, 0b11100000, //92 (backslash) 0b00000000, 0b10000000, 0b01000000, 0b00100000, 0b00010000, 0b00001000, 0b00000000, //93 ] 0b00111000, 0b00001000, 0b00001000, 0b00001000, 0b00001000, 0b00001000, 0b00111000, //94 ^ 0b00100000, 0b01010000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //95 _ 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b11111000, //96 ` 0b10000000, 0b01000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, //97 a 0b00000000, 0b01100000, 0b00010000, 0b01110000, 0b10010000, 0b01100000, 0b00000000, //98 b 0b10000000, 0b10000000, 0b11100000, 0b10010000, 0b10010000, 0b11100000, 0b00000000, //99 c 0b00000000, 0b00000000, 0b01110000, 0b10000000, 0b10000000, 0b01110000, 0b00000000, // 100 d 0b00010000, 0b00010000, 0b01110000, 0b10010000, 0b10010000, 0b01110000, 0b00000000, //101 e 0b00000000, 0b01100000, 0b10010000, 0b11110000, 0b10000000, 0b01110000, 0b00000000, //102 f 0b00110000, 0b01000000, 0b11100000, 0b01000000, 0b01000000, 0b01000000, 0b00000000, //103 g 0b00000000, 0b01100000, 0b10010000, 0b01110000, 0b00010000, 0b00010000, 0b01100000, //104 h 0b10000000, 0b10000000, 0b11100000, 0b10010000, 0b10010000, 0b10010000, 0b00000000, //105 i 0b00000000, 0b00100000, 0b00000000, 0b00100000, 0b00100000, 0b00100000, 0b00000000, //106 j 0b00000000, 0b00010000, 0b00000000, 0b00010000, 0b00010000, 0b00010000, 0b01100000, //107 k 0b10000000, 0b10010000, 0b10100000, 0b11000000, 0b10100000, 0b10010000, 0b00000000, //108 l 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00000000, //109 m 0b00000000, 0b00000000, 0b01010000, 0b10101000, 0b10101000, 0b10101000, 0b00000000, //110 n 0b00000000, 0b00000000, 0b01100000, 0b10010000, 0b10010000, 0b10010000, 0b00000000, //111 o 0b00000000, 0b00000000, 0b01100000, 0b10010000, 0b10010000, 0b01100000, 0b00000000, //112 p 0b00000000, 0b00000000, 0b01100000, 0b10010000, 0b11110000, 0b10000000, 0b10000000, //113 q 0b00000000, 0b00000000, 0b01100000, 0b10010000, 0b11110000, 0b00010000, 0b00010000, //114 r 0b00000000, 0b00000000, 0b10111000, 0b01000000, 0b01000000, 0b01000000, 0b00000000, //115 s 0b00000000, 0b00000000, 0b01110000, 0b01000000, 0b00010000, 0b01110000, 0b00000000, //116 t 0b01000000, 0b01000000, 0b11100000, 0b01000000, 0b01000000, 0b01000000, 0b00000000, // 117u 0b00000000, 0b00000000, 0b10010000, 0b10010000, 0b10010000, 0b01100000, 0b00000000, //118 v 0b00000000, 0b00000000, 0b10001000, 0b10001000, 0b01010000, 0b00100000, 0b00000000, //119 w 0b00000000, 0b00000000, 0b10101000, 0b10101000, 0b01010000, 0b01010000, 0b00000000, //120 x 0b00000000, 0b00000000, 0b10010000, 0b01100000, 0b01100000, 0b10010000, 0b00000000, //121 y 0b00000000, 0b00000000, 0b10010000, 0b10010000, 0b01100000, 0b01000000, 0b10000000, //122 z 0b00000000, 0b00000000, 0b11110000, 0b00100000, 0b01000000, 0b11110000, 0b00000000, //123 { 0b00100000, 0b01000000, 0b01000000, 0b10000000, 0b01000000, 0b01000000, 0b00100000, //124 | 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, //125 } 0b00100000, 0b00010000, 0b00010000, 0b00001000, 0b00010000, 0b00010000, 0b00100000, //126 ~ 0b00000000, 0b00000000, 0b01000000, 0b10101000, 0b00010000, 0b00000000, 0b00000000, //127 DEL 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000 }; // put the MCU to sleep JUST before the CompA ISR goes off ISR(TIMER1_COMPB_vect, ISR_NAKED) { sei(); sleep_cpu(); reti(); } //================================== //This is the sync generator and raster generator. It MUST be entered from //sleep mode to get accurate timing of the sync pulses ISR (TIMER1_COMPA_vect) { int x, screenStart ; //start the Horizontal sync pulse PORTD = syncON; //update the current scanline number LineCount++; //begin inverted (Vertical) synch after line 247 if (LineCount==248) { syncON = 0b00000001; syncOFF = 0; } //back to regular sync after line 250 if (LineCount==251) { syncON = 0; syncOFF = 0b00000001; } //start new frame after line 262 if (LineCount==263) LineCount = 1; //adjust to make 5 us pulses _delay_us(3); //end sync pulse PORTD = syncOFF; if (LineCount < ScreenBot && LineCount >= ScreenTop) { //compute offset into screen array //screenindex = screen + ((LineCount - ScreenTop) << 4) + ((LineCount - ScreenTop) << 3); //compute offset into screen array //screenStart = ((LineCount - ScreenTop) << 4) + ((LineCount - ScreenTop) << 3) ; screenStart = (LineCount - ScreenTop) * bytes_per_line; //center image on screen _delay_us(7); //blast the data to the screen // We can load UDR twice because it is double-bufffered UDR0 = screen[screenStart] ; UCSR0B = _BV(TXEN0); UDR0 = screen[screenStart+1] ; for (x = 2; x < bytes_per_line; x++) begin while (!(UCSR0A & _BV(UDRE0))) ; UDR0 = screen[screenStart+x] ; end UCSR0B = 0 ; } } //================================== //plot one point //at x,y with color 1=white 0=black 2=invert void video_pt(char x, char y, char c) { //each line has 18 bytes //calculate i based upon this and x,y // the byte with the pixel in it //int i = (x >> 3) + ((int)y<<4) + ((int)y<<1); int i = (x >> 3) + (int)y * bytes_per_line ; if (c==1) screen[i] = screen[i] | pos[x & 7]; else if (c==0) screen[i] = screen[i] & ~pos[x & 7]; else screen[i] = screen[i] ^ pos[x & 7]; } //================================== //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) { int e; signed int dx,dy,j, temp; signed char s1,s2, xchange; signed int x,y; x = x1; y = y1; //take absolute value if (x2 < x1) { dx = x1 - x2; s1 = -1; } else if (x2 == x1) { dx = 0; s1 = 0; } else { dx = x2 - x1; s1 = 1; } if (y2 < y1) { dy = y1 - y2; s2 = -1; } else if (y2 == y1) { dy = 0; s2 = 0; } else { dy = y2 - y1; s2 = 1; } xchange = 0; if (dy>dx) { temp = dx; dx = dy; dy = temp; xchange = 1; } e = ((int)dy<<1) - dx; for (j=0; j<=dx; j++) { video_pt(x,y,c); if (e>=0) { if (xchange==1) x = x + s1; else y = y + s2; e = e - ((int)dx<<1); } if (xchange==1) y = y + s2; else x = x + s1; e = e + ((int)dy<<1); } } //================================== // put a big character on the screen // c is index into bitmap void video_putchar(char x, char y, char c) { char i; char y_pos; uint8_t j; for (i=0;i<7;i++) { y_pos = y + i; j = pgm_read_byte(((uint32_t)(ascii)) + c*7 + i); video_pt(x, y_pos, (j & 0x80)==0x80); video_pt(x+1, y_pos, (j & 0x40)==0x40); video_pt(x+2, y_pos, (j & 0x20)==0x20); video_pt(x+3, y_pos, (j & 0x10)==0x10); video_pt(x+4, y_pos, (j & 0x08)==0x08); } } //================================== // put a string of big characters on the screen void video_puts(char x, char y, char *str) { char i; for (i=0; str[i]!=0; i++) { video_putchar(x,y,str[i]); x = x+6; } } //================================== // put a small character on the screen // x-coord must be on divisible by 4 // c is index into bitmap void video_smallchar(char x, char y, char c) { char mask; //int i=((int)x>>3) + ((int)y<<4) + ((int)y<<1); int i=((int)x>>3) + (int)y * bytes_per_line ; if (x == (x & 0xf8)) mask = 0x0f; //f8 else mask = 0xf0; uint8_t j = pgm_read_byte(((uint32_t)(smallbitmap)) + c*5); screen[i] = (screen[i] & mask) | (j & ~mask); j = pgm_read_byte(((uint32_t)(smallbitmap)) + c*5 + 1); screen[i+bytes_per_line] = (screen[i+bytes_per_line] & mask) | (j & ~mask); j = pgm_read_byte(((uint32_t)(smallbitmap)) + c*5 + 2); screen[i+bytes_per_line*2] = (screen[i+bytes_per_line*2] & mask) | (j & ~mask); j = pgm_read_byte(((uint32_t)(smallbitmap)) + c*5 + 3); screen[i+bytes_per_line*3] = (screen[i+bytes_per_line*3] & mask) | (j & ~mask); j = pgm_read_byte(((uint32_t)(smallbitmap)) + c*5 + 4); screen[i+bytes_per_line*4] = (screen[i+bytes_per_line*4] & mask) | (j & ~mask); } //================================== // 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) { char i; x = x & 0b11111100; //make it divisible by 4 for (i = 0; str[i] != 0; i++) { if (str[i] >= 0x30 && str[i] <= 0x3a) video_smallchar(x, y, str[i] - 0x30); else video_smallchar(x, y, str[i]-0x40+12); x += 4; } } //================================== //return the value of one point //at x,y with color 1=white 0=black 2=invert char video_set(char x, char y) { //The following construction //detects exactly one bit at the x,y location // int i = (x>>3) + ((int)y<<4) + ((int)y<<3); int i = (x>>3) + (int)y * bytes_per_line ; return (screen[i] & 1<<(7-(x & 0x7))); } /*/=== fixed point mult =============================== int multfix(int a, int b) { int result1 = a * b; int result2 = (a>>8) * (b>>8); return (result2 << 8) | (result1 >> 8); } */ //=== fixed conversion macros ========================================= #define int2fix(a) (((int)(a))<<8) //Convert char to fix. a is a char #define fix2int(a) ((signed char)((a)>>8)) //Convert fix to int. a is an int #define float2fix(a) ((int)((a)*256.0)) //Convert float to fix. a is a float #define fix2float(a) (((float)(a))/256.0) //Convert fix to float. a is an int //=== animation stuff ================================================== unsigned int x, y; int vx, vy, g, drag; char cu1[]="Cornell ECE 4760"; char cu2[]="COPYRIGHT:2012"; /////////////// //================================== // set up the ports and timers int main() { //init timer 1 to generate sync //OCR1A = lineTime; //One NTSC line // TIMER 1: OC1* disconnected, CTC mode, fosc/1 (20MHz), OC1A and OC1B // interrupts enabled TCCR1B = _BV(WGM12) | _BV(CS10); OCR1A = LINE_TIME; // time for one NTSC line OCR1B = SLEEP_TIME; // time to go to sleep TIMSK1 = _BV(OCIE1B) | _BV(OCIE1A); //init ports DDRD = 0x03; //video out // USART in MSPIM mode, transmitter enabled, frequency fosc/4 UCSR0B = _BV(TXEN0); UCSR0C = _BV(UMSEL01) | _BV(UMSEL00); UBRR0 = 1 ; //initialize synch constants LineCount = 1; syncON = 0b00000000; syncOFF = 0b00000001; //Print "CORNELL" message video_puts(30,2,cu1); //Print "Copyright" message video_putsmalls(screen_width-70,screen_height-10,cu2); //side lines #define width screen_width-1 #define height screen_height-1 //video_line(0,0,0,height,1); video_line(width,0,width,height,1); video_line(0,10,width,10,1); video_line(0,0,width,0,1); video_line(0,height,width,height,1); //video_line(0,0,width,height,1); //init animation // initial position x = int2fix(20); y = int2fix(40); // initial velocity vx = float2fix(2.5); vy = float2fix(0.0); // gravity and drag g = float2fix(0.02); drag = float2fix(0.004); video_pt(fix2int(x)-1,fix2int(y),2); video_pt(fix2int(x)+1,fix2int(y),2); video_pt(fix2int(x),fix2int(y)-1,2); video_pt(fix2int(x),fix2int(y)+1,2); //init musical scale note = 0; musicT = 0; //use OC0A (pin B.3) for music DDRB = (1< 15) { //each note 1/4 second musicT = 0; OCR0A = notes[note++] ; if (note>18) note = 0; //test for end of scale } //animation //erase old ball using XOR mode video_pt(fix2int(x)-1,fix2int(y),2); video_pt(fix2int(x)+1,fix2int(y),2); video_pt(fix2int(x),fix2int(y)-1,2); video_pt(fix2int(x),fix2int(y)+1,2); // new vel = old vel + acceleration*dt (dt=1) vy = vy + g - multfix(drag,vy); vx = vx - multfix(drag,vx); // new pos = old pos + velocity*dt (dt=1) x = x + vx; y = y + vy; // Bounds check -- fixed notation if (x>0x9e00) { vx = -vx; x=0x9e00; } // right edge if (x<0x0200) { vx = -vx; x=0x0200; } // left edge if (y>0xc700) { vy = -vy; y=0xc700; } // bottom edge video_pt(fix2int(x)-1,fix2int(y),2); video_pt(fix2int(x)+1,fix2int(y),2); video_pt(fix2int(x),fix2int(y)-1,2); video_pt(fix2int(x),fix2int(y)+1,2); ///////////////////////////////////////// // add this line to execute code exactly once per frame // comment it out for max execution speed while (LineCount != ScreenTop) ; } //line 231 } //for } //main