mod 6 counter 0 IC 74161

Thread Starter

daniel000

Joined Apr 3, 2011
17
Hi guys

I have noticed on this site there are a few wiring diagrams. I'm just wondering if anyone would be able to assist me on wiring up the following.

I have to wire up a mod 6 counter using 4 bit binary.

The image i am following says to use a IC 74161 and it also uses a NAND gate which will need a 74LS00 chip. i have a dip switch for the inputs and resistors. Im just wondering if there is a similar situation that i could follow to assist me in wiring this up on my breadboard

cheers
daniel
 

Georacer

Joined Nov 25, 2009
5,182
Do you know what you must do with your parts? The idea is to wire the circuit so that the counter will reset asynchronously when it reaches the count of 7, restarting the count from 0.
 

Thread Starter

daniel000

Joined Apr 3, 2011
17
Thanks for the reply guys.
And yes I need 6 cycles. With the parts, I have a dip switch which will act as 4 inputs and I will obviously have a count as one , clock pulse and there was also another but I can't remember ATM, there is also four outputs which will be the LEDs. Now I'm Also confused as to how to wire the dipswitch. With the switch do resistors go from the switches to ground and also to Vcc ? And then off too the inputs on to the chip? I'm also confused as to how to wire the NAND chip to the other?
 

Georacer

Joined Nov 25, 2009
5,182
What do you need the inputs for? The counter typically doesn't use any input, except maybe for a reset button, which you haven't mentioned.
 

Thread Starter

daniel000

Joined Apr 3, 2011
17
So guys,

There are the four outputs D C B and A. The diagram then has a NAND gate with the inputs attached to outputs C and A which the output of the NAND goes to LOAD which then connects back to the counter.

There are also 3 other parts connected, Count which is equal to 1, Clear whihch is equal to 1 and Clock pulse.

I then have inputs , which on this diagram are equal to - and there are four of these.

im just confused as to how certain things need to be wired
 

Georacer

Joined Nov 25, 2009
5,182
You have at your hands a counter with a parallel load function. It an extra function that shouldn't bother you for now. All you need is the clock input, and the Count and Clear inputs tied to HIGH. You can ignore the 4 input pins completely if you want. A good practice is to tie them to Ground, though.

As for the Load input, remember that you want to reset at 6, not 5. You have wired the AND gate to trigger at 5.
 

Thread Starter

daniel000

Joined Apr 3, 2011
17
Thanks for that

So with the two diagrams that I have, especially the second one with the NAND gate, does my wiring look to be OK? Mainly with pin placement and the dip switches and how i have wired that? (i think the function table is wrong for this design)

Also, you mentioned the four input pins are irrelevant, are these four the inputs that are connected to the switch? if so, these should still connected as no input is regarded as one isnt it? and these need to be zero?

as for the clock input, and the Count and Clear inputs that need to be tied to HIGH ( connected to Vcc ? ) So far I have, count connected to high dont I? I have pins 7 to 10 connected then 10 to High, is that OK? And for Clear and CP, do i just run wires from pins 1 and 2 to Vcc?

Also you mentioned i have a AND gate wired up, i thought i needed a NAND lol was this just a typo? and im confused on how to wire it to trigger at 6 where i have it triggered at 5

thank you for your help, i think im almost done just confused on these last points.

cheers
daniel
 

Georacer

Joined Nov 25, 2009
5,182
As you correctly pointed, I meant NAND, not AND. In order to make it trigger to 6 you must connect its inputs to C and B, not C and A, because the binary representation of 6 is 0110.

Personally I don't feel I can help you with the wiring on your breadboard. That can be only done in person. The things that can go wrong are just too many.
 

Thread Starter

daniel000

Joined Apr 3, 2011
17
Ok thank you

So even though the diagram has the NAND gate connected to C and A, i should not have this wired up like that?

Hopefully someone can have a look at the diagrams on page one and see if that wiring matches the ones on paper

Also, does the dip switch look like it is wired up correctly?
 

Georacer

Joined Nov 25, 2009
5,182
As I said: The diagram shows a NAND gate wired to Load the counter when it reaches 5. You want it to Load when it reaches 6.
 

Thread Starter

daniel000

Joined Apr 3, 2011
17
alright sweet, il just leave it the way it is

anyone else able to shed some light on the other parts that are wired up?


like the dip switch and other parts of the breadboard?

thanks
daniel
 

Wendy

Joined Mar 24, 2008
23,421
I see no filter caps. For static digital they aren't as important, if this circuit had an internal clock they would be more important.

I will disagree with beenthere on one point, neatness is very important. You've done a good job there. It helps spot mistakes (making them easier to see), keeps wires short so they don't act like antennas, and in general improve your chances of having the circuit work the first time you power it up.

http://forum.allaboutcircuits.com/showthread.php?t=53866

The vast majority of projects I was careful to lay out well worked the first time, unlike some of the rats nests from my early days.
 

Thread Starter

daniel000

Joined Apr 3, 2011
17
Thanks mate

We dont require any filter caps for this, but thanks anyway.

As for my wiring does this look ok compared to the written diagrams? How does my dip switch look, is that wired up ok?

cheers guys
 
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