help in presetting

how can i preset this to display a 12 - hour clock units digit

1 2 3 4 5 6 7 8 9 0 1 2 1 2 3 4 5 6 7 8 9 0 1 2

Hi,


It looks like you dont have all your 'D' inputs going to ground, which would cause a preset of zero (0) which is what you want when the counter reaches a count of 10, which is 0101 binary. If you are activating the preset with the AND gate this should work ok, as long as the preset is asynchronous.
You could also use a 74LS90 and that would be simpler.

ok... thanks