rentshare_display.c

#define BIT_ISSET( flags, flag ) ( ( (flags) & (flag) ) == (flag) )

#define SegA 9
#define SegB 10
#define SegC 11
#define SegD 12
#define SegE 13
#define SegF 8
#define SegG 7

#define Dig0 34
#define Dig1 32
#define Dig2 30
#define Dig3 28
#define Dig4 26
#define Dig5 24
#define Dig6 22

#define REFRESH_RATE 1

#define SERIAL_TERM_CHAR 0
#define DISPLAY_BUFFER_SIZE 7

const char seg_num_to_pin[]    = { SegA, SegB, SegC, SegD, SegE, SegF, SegG };
const char digit_num_to_pin[]  = { Dig0, Dig1, Dig2, Dig3, Dig4, Dig5, Dig6 };
const char seg_num_to_bit[]    = { 0b1000000, 0b0100000, 0b0010000, 0b0001000, 0b0000100, 0b0000010, 0b0000001 };
const char char_to_seg_map[] = {
  /* digits */
  0b1111110 /*0*/, 0b0110000 /*1*/, 0b1101101 /*2*/, 0b1111001 /*3*/, 0b0110011 /*4*/,
  0b1011011 /*5*/, 0b0011111 /*6*/, 0b1110000 /*7*/, 0b1111111 /*8*/, 0b1110011 /*9*/,

  /* letters */
  0b1110111 /*A*/, 0b0011111 /*B*/, 0b1001110 /*C*/, 0b0111101 /*D*/, 0b1001111 /*E*/, 0b1000111 /*F*/,
  0b1111011 /*G*/, 0b0110111 /*H*/, 0b0000110 /*I*/, 0b0111000 /*J*/, 0b1111110 /*K*/, 0b0001110 /*L*/,
  0b0110111 /*M*/, 0b0010101 /*N*/, 0b1111110 /*O*/, 0b1100111 /*P*/, 0b1111110 /*Q*/, 0b0000101 /*R*/,
  0b1011011 /*S*/, 0b1110000 /*T*/, 0b0111110 /*U*/, 0b0111110 /*V*/, 0b1111110 /*W*/, 0b1100111 /*X*/,
  0b0110111 /*Y*/, 0b0110000 /*Z*/,

  /* blank */
  0b0000000 };

char display_buffer[DISPLAY_BUFFER_SIZE] = { '8', '8', '8', '8', '8', '8', '8' };

void setup() {
	for ( char i = 0; i < sizeof( seg_num_to_pin ); i++ )
		pinMode( seg_num_to_pin[i], OUTPUT );

	for ( char i = 0; i < sizeof( digit_num_to_pin ); i++ )
		pinMode( digit_num_to_pin[i], OUTPUT );

	clear();
	Serial.begin(9600);
}

void clear() {
	for ( char i = 0; i < sizeof( seg_num_to_pin ); i++ )
		digitalWrite( seg_num_to_pin[i], LOW );

	for ( char i = 0; i < sizeof( digit_num_to_pin ); i++ )
		digitalWrite( digit_num_to_pin[i], HIGH );
}

char asciiToSegMap( char c ) {
	//Serial.print(c - 48,DEC);
	if ( c <= 57 && c >= 48 )
		return char_to_seg_map[ c - 48 ];
	if ( c <= 122 && c >= 97 )
		return char_to_seg_map[ c - 87 ];
	if ( c <= 90 && c >= 65 )
		return char_to_seg_map[ c - 55 ];
	if ( c == 32 )
		return char_to_seg_map[ sizeof( char_to_seg_map ) - 1 ];

	return char_to_seg_map[ sizeof( char_to_seg_map ) - 1 ];
}

bool digitContainsSeg( char c, char seg ) {
	return BIT_ISSET( asciiToSegMap( c ), seg_num_to_bit[ seg ] );
}

void draw() {
	for ( char seg_num = 0; seg_num < sizeof( seg_num_to_pin ); seg_num++ ) {

		for ( char j = 0; j < sizeof( display_buffer ); j++ )
			digitalWrite( digit_num_to_pin[j], !digitContainsSeg( display_buffer[j], seg_num ) );

		digitalWrite( seg_num_to_pin[ seg_num ], HIGH );

		delay( REFRESH_RATE );

		digitalWrite( seg_num_to_pin[ seg_num ], LOW );
	}
}

void loop() {
	draw();

	if ( Serial.available() > 0 ) {
		// read the incoming byte:
		char input_buffer[DISPLAY_BUFFER_SIZE] = { 0, 0, 0, 0, 0, 0, 0 };
		Serial.readBytesUntil( SERIAL_TERM_CHAR, input_buffer, sizeof( input_buffer ) );
		memcpy( display_buffer, input_buffer, sizeof( display_buffer ) );
		// say what you got:
		Serial.print("I received: ");
		Serial.print( display_buffer );
	}

	/*
	t++;
	if ( t % 10000 ) {
		for ( char c = 0; c < 1000; c++ ) {
			char pos = 6;
			if ( display[pos] == 9 )
				while ( display[pos] == 9 ) {
					display[pos] = 0;
					pos--;
				}
			display[pos]++;
		//	for ( char i = 0; i < 1000 / ( REFRESH_RATE * 7 ); i++ )
				draw();
		}
	}*/
}