Hi there, i could use some help with an Electronic dice. I have built an A-stable, got the counter (4517) and the decoder (4511) wired up correctly, however there seems to be some interfacing problems, as it dose not work ops: .
I know it is a simple circuit, but i just cant get it to work! If you could help, here is what i wanted it to do;
Count from 1 - 6 (hence 4517 - for the preset to 1 reset)
Count at 1000 times a second (i have already worked out how to do this with a 555 astable)
Be able to freeze the number it is on at any time by pressing a button (whenever i try to use a button, it randomly changes the numbers on the 7 segment display, usualy not even to number patterns :roll:
Oh, and how could i get the counter to stop at 6? i tryed having some and gates make the reset high when it go to 7 in binary, but it didnt work

HELP!11 :P

 

It is difficult to advise you without having a circuit to look at. And, I don't have a data sheet for the 4517.

Did you install bypass capacitors, ie. 100 nF caps across the IC supply pins? See the attachment.
If these are not provided, strange effects can occur due to coupling via the supply line.

The attachment is an ED that I did some time ago. It is similar to yours in that it counts from 1 to 7 and then is preset to 1, so it effectively counts from 1 to 6 since it does not remain in state 7 very long.

Note that one or two dice can be selected with the switch. So there are 2 counters and I did not use 7 segment displays, I used LEDs configured as a dice is configured.

Len

Attached Images

Digital_Dice_1_109.gif (11.7 KB, 561 views)

 

Hmm ok, ill try to post a schematic..... anyone know a good prog for circuit drawing?

 

I did the above in PowerPoint. Save it as a .ppt initially and then when ready to submit, Save as a .gif