Im not actually wanting help with code at present, but rather suggestions of technique, from which I can then go away and play with the code to see if I can make it work,
Heres the premise -
I will have a 4 digit decimal number displayed on an LCD, and also saved as a variable to be used for other purposes. I will have three buttons - UP, DOWN, and SELECT.
The SELECT button will be used to determine the position of a cursor beneath one of the four digits.
Whichever digit the cursor is under, is the number to be incremented (by the UP button) or decremented (by the DOWN) button.
Now, the inc/dec for a number isnt too much of a trouble,
but, theres a bit more to it! If the selected number rolls over, I need the next number to inc/dec by one, i.e. if incrementing the second digit, it rolls over 9 to 0, then the first must increment. Likewise for decrement, if the second for example rolls over 0 to 9 then the third must decrement by 1
Essentially like a tally counter, up or down, but with the position being worked on selectable. If the whole number rolls over, ie 9999 to 0000 or 0000 to 9999, then thats fine.
It seems to me there is probably a very simple way of implementing this, but I cant think how
Ive searched for examples of code, but I can only find inc/dec methods without the selectable digit
As I say, Im only looking for direction to a technique to then go and study