7segment displays with max7219 chip counting

hello all,

i have just started using arduino from various other C based controllers and have a uni project that im trying to sort out asap. i have 2 7segment displays mutiplexed up and working fine, but im trying to work out how i can have a potentiometer connected to control the digits that have been displayed. The hardwear works fine its just my coding abilities that i am having trouble with. In fact i have no idea how to start. any help would be gratefully appreciated

cheers

adknott

I’d start by writing a function

// set/unset segments of display identified by display_id
void seven_seg_contol(int display_id, uint8_t bits){
for(uint8_t i = 0; i < 8; i++){
if(1 && bits >> i){
// light up the ith segment of display_id
}
else{
// unlight the ith segment of display_id
}
}

Then define constants for each digit.
const uint8_t ONE = 0b00010001; // just for instance I don’t really know which bits to be on or off
const uint8_t TWO = 0b01111001; // just for instance I don’t really know which bits to be on or off

Then write a higher level function display

void seven_seg_display(uint8_t two_digit_num){
// ones digit
switch(two_digit_num % 10){
case 1:
seven_set_control(ONES_DIGIT, ONE);
break;

}
// tens digit
switch(two_digit_num / 10){
case 1:
seven_set_control(TENS_DIGIT, ONE);
break;

}
}