//***********************************************************************************
uint8_t main()
{
uint16_t sum=0;
uint8_t digit=0;
//set port bits 4-7 B as outputs
DDRB = 0xF0;
PORTB = 0x00;
while(1){
//insert loop delay for debounce
_delay_ms(3);
//make PORTA an input port with pullups
DDRA = 0x00;
PORTA = 0xFF;
//enable tristate buffer for pushbutton switches
PORTB |= 0x70;
//now check each button and increment the count as needed
for(uint8_t i=0; i<8; ++i){
sum += chk_buttons(i) << i;
}
//disable tristate buffer for pushbutton switches
PORTB &= 0x5F;
//bound the count to 0 - 1023
if(sum>1023){
//sum = (sum+1)%1024;
sum = 0;
segment_data[0] = 0x01;
segment_data[1] = 0x00;
segment_data[2] = 0x00;
segment_data[3] = 0x00;
segment_data[4] = 0x00;
}
// sum %= 1024;
//break up the disp_value to 4, BCD digits in the array: call (segsum)
segsum(sum);
//make PORTA an output
DDRA = 0xFF;
//prevent ghosting
PORTA = 0x00;
//send 7 segment code to LED segments
//TODO: why did I put dec_to_7seg here and it works?
PORTA = dec_to_7seg[segment_data[digit]];
//send PORTB the digit to display
PORTB = ((0x8<<4) & PORTB)|(digit<<4);
//update digit to display
digit = (++digit)%5;
}//while
return 0;
}//main
//***********************************************************************************
// The Main function initializes PORT A B E and calculates for the result of sum, it changes
// the value by pushing the button switch S1 and S6. Pushing S1 means to increment or
// decrement 2, linghting D1 and D2 on bar graph; Pushing S6 means to increment or
// decrement 4, linghting D1-4
//***********************************************************************************
int main() {
int16_t sum = 0; //the value of sum
int8_t rawkeypressed = 0;
uint8_t button;
uint8_t past_state = 0;
uint8_t mode; // 1 -- in mode 1; 2 -- in mode 2; 4 -- in mode 4
//set PB[7:4] as output for 74HC138 decoder;
//set PB[3:0] to turn on MISO as input, and turn on SS, MOSI, SCLK as output
DDRB = 0xF7;
DDRE |= 0xC0; // Turn on CLK_INH, SH/LD as output 11000000
DDRA = 0x00; //set port A all input for 7-segment
tcnt0_init(); //initalize counter timer zero
spi_init(); //initalize SPI port
sei(); //enable interrupts before entering loop
while(1){
_delay_ms(3); //delay 3 ms
PORTA = 0xFF; //set port A to be with pullups
PORTB = 0x70; //set the decoder
uint8_t i;
//use i to check out which button is pushed
for (i = 6; i < 8; i++){
//push the button
if (chk_buttons(i)) { //if push button S6 or S7
button = i;
if (button == 6) { //push S6
if (past_state == 6) mode = 1; //push S6 twice
else if (past_state == 7) {
if (mode == 0) mode = 2;
else mode = 0; //push S6 and then push S7
}
else { // only push S6 one time
mode = 2;
past_state = button;
}
}//if
else if (button == 7) { //push S7
if (past_state == 7) mode = 1; //push S7 twice
else if (past_state == 6) mode = 0; //push S7 and then push S6
else { // only push S7 one time
mode = 4;
past_state = button;
}
}//if
else { // come back to mode 1
mode = 1;
}
}//if
}//for
switch (mode) {
case 0: coefficient = 0; break;
case 1: coefficient = 1; past_state = 0; display_count &= 0x00; break;
// low bytes stand for counting 1
case 2: coefficient = 2; display_count &= 0x00; display_count |= 0x03; break;
// low bytes stand for counting 4
case 4: coefficient = 4; display_count &= 0x00; display_count |= 0x0F; break;
}
//only showing 0-1023, sum is effected by count, sign and x2/x4
if ((sum < 1024) && (sum >= 0)) {sum += count * count_sign * coefficient;}
//if the sum is larger than the max value 1024, subtract 1023 and show the remaining
else if (sum >= 1024){sum -= 1023;}
else if (sum < 0) {sum += 1024;}
if (sum < 10) {
a[0] = sum%10; //get the number of units
a[1] = 10;
a[3] = 10;
a[4] = 10;
}
else if (sum < 100) {
a[0] = sum%10; //get the number of units
a[1] = sum/10%10; //get the number of tens
a[3] = 10;
a[4] = 10;
}
else if (sum <1000) {
a[0] = sum%10; //get the number of units
a[1] = sum/10%10; //get the number of tens
a[3] = sum/100%10; //get the number of hundreds
a[4] = 10;
}
else {
a[0] = sum%10; //get the number of units
a[1] = sum/10%10; //get the number of tens
a[3] = sum/100%10; //get the number of hundreds
a[4] = sum/1000; //get the number of thousands
}
//send sum to display 7-segement
segment_value(a);
//reset counter
count = 0;
//use buffer to forbid from assigning value of button
PORTB = 0x5F;
//set port A all output for 7-segment
DDRA = 0xFF;
//reset PORTA
PORTA = 0x00;
//reset button state for releasing
rawkeypressed = 0;
//send value of 4 digit segments to display
segment_sum(SEG);
}//while
}//main
