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ali8tor
09-09-2012, 08:21 AM
hi

Im trying to make a bcd counter using 4510 ic that counts up to 60 and resets which is displayed on two 7 segment displays (4511 ic). I seriously need help.

thanks

bertus
09-09-2012, 10:41 AM
Hello,

Can you show us what you have got upto now?
(post a schematic)
Can you tell us where you got stuck?

Bertus

ScottWang
09-09-2012, 06:38 PM
Do you just want to count up to 60, and no count down?
If do so, then you can use CD4518, that's easier than CD4510, CD4510 is designed for Count up/down, it's needs more control.

BMorse
09-09-2012, 09:06 PM
take a look here and see if you can sort your issue out >> http://www.doctronics.co.uk/4511.htm

ali8tor
09-11-2012, 07:10 AM
Hi

I just need it to count to 60 and reset, i've connected up two 4510 ic to two 4511. ive attached the schematic, cheers

bertus
09-11-2012, 07:51 AM
Hello,

The schematic is to tiny to read properly.
What I can see is that you use two separate pulse sources.
This is not correct.
You can feed the carry of the fast counter to the clock of the slow counter.
Also I do not see the detection of the number 60 in your schematic.

Bertus

ali8tor
09-11-2012, 08:07 AM
oh yup, i actually don't know how to wire up the bcd counter in a way where it counts up to 60, the circuit right now counts to 99 and resets. am i suppose to use logic gates to make it count to 60?

MrChips
09-11-2012, 08:11 AM
Do you want the counter to stop when 60 is reached?
Do you want the counter to continue counting 59-60-00-01?
Or do you want the counter to count 58-59-00-01...?

bertus
09-11-2012, 08:12 AM
Hello,

Wich bits show a 6 at the high (slow) counter?
Detect them to reset the high (slow) counter.

Bertus

ali8tor
09-11-2012, 08:19 AM
Hi

I would like it to go 59-60-00-01?

thanks

ali8tor
09-11-2012, 08:21 AM
Hi bertus

i think it would detect 0110?

MrChips
09-11-2012, 08:26 AM
Hi

I would like it to go 59-60-00-01?

thanks
Now, be careful. If you are counting seconds or minutes, you will be counting 61 seconds or minutes.

ali8tor
09-11-2012, 09:03 AM
Hello there

I managed to fix it up a bit and now the circuits counting to 59 and resetting which is close to what i want. But i need to see decimal 60 before it resets and starts counting again. I've attached the circuit

thanks guys :)

MrChips
09-11-2012, 09:06 AM
Then you want it to count 58-59-60-01-02...

which is a lot easier to do with a microcontroller.

ali8tor
09-11-2012, 09:08 AM
exactly, would you know how to make the circuit do that?

thankyou

elec_mech
09-11-2012, 01:02 PM
To do what you've asked, you need to have the circuit reset at 61. You're resetting at 60 so when the count turns from 59 to 60, you'll see 59 then 00.

To do this, I'd suggest a CD4078 using the NOR output. This accepts eight inputs. You'll feed the outputs from both CD4510s to the CD4078. You'll need to add some NOT gates.

Tens digit:
A: Straight to CD4078
B: Through NOT gate to CD4078
C: Through NOT gate to CD4078
D: Straight to CD4078

Ones digit:
A: Through NOT gate to CD4078
B: Straight to CD4078
C: Straight to CD4078
D: Straight to CD4078

So, Tens = Decimal 6, binary 0110 converts to 0000 into CD4078, Ones = Decimal 1, binary 0001 converts to 0000 into CD4078.

The CD4078 will then output a logic 1 on the NOR output which you need to feed to the reset pins on BOTH CD4510s.

MrChips
09-11-2012, 01:17 PM
Not quite correct. You need to preload (reset) to 01.

elec_mech
09-11-2012, 03:13 PM
Not quite correct. You need to preload (reset) to 01.

Whoops, sorry, I missed the 60 to 01 and thought I saw 60, 00, 01. Thank you MrChips.

In that case, the output of the CD4078 goes to the reset pin of the CD4510 for the tens digit and to pin 1 of the CD4510 for the ones digit. The preset inputs on CD4510 for the ones digit need to be set to 0001 where P1 is high and P2-P4 are low. Then the display will show 59, 60, 01, 02.

Also, your schematic shows a 60Hz clock. Are you counting in seconds or something else? If the former, it should be 1Hz.

MrCarlos
09-11-2012, 05:52 PM
Hello ali8tor

If you want to see the 60 in the Displays you must reset on 61, otherwise you never will see the 60.
Let me named the Qs Outputs As:

Units Counter: Q8, Q4, Q2, Q1,
Tens Counter: Q80, Q40, Q20, Q10.
So, The Qs Outputs are true when It Is High.
Therefore: you Must detect when the counter Reach: 0110 0001(Binary) 61(Decimal).
The input Reset is True when it si high.

The AND gate statemente say:
Until All inputs are high its output will be high.
You could use one 3 input AND gate to detect our 61 and its output connected to the MR on the counters.

Take a look the attached image. See if it is good for you.
This counter will cycle from 0 to 60 and start again.

regards
at your service

elec_mech
09-11-2012, 06:35 PM
Hi MrCarlos - much more elegant using the 3-input AND gate than the 8-input NOR gate with NOT gates I suggested. I love this site - I'm always learning something new or another way to solve a problem.

A couple of notes - as MrChips pointed out to me, the OP wants the output to look like 59, 60, 01, 02, . . . so the OP will need to use the preset inputs. On further thought, the OP should probably use the presets on the tens place 4510 as well and tie P1-P4 low. In this way, the OP can reset the circuit to 01 instead of 00 using a button if desired.

I also notice you tie the CO pin from the ones 4510 to the clock pin of the tens 4510 - I assume this is a form of ripple counting? I just noticed the OP did this in the last schematic posted as well. The datasheet shows using a CD4071 fed by the clock signal and the CO from the ones IC and outputting into the clock input of the tens 4510. I would suggest the OP use parallel clocking to avoid extra parts - connect the clock signal to both clock pins of the 4510s. Connect pin 7 (CO) from the ones 4510 to pin 5 (CI) of the tens 4510.

MrCarlos
09-12-2012, 07:05 AM
Hello everybody

Another way.
Let me supose That We know what the Magnitude Comparator 4063 does.
But if We dont know let me say a few words:
All this IC does is to compare two numbers, A and B, and say if A>B or A=B or A<B that is all.

So, with the circuit in the picture we can meet the required by the OP.
Of course We need to add some extra circuitry.
We could drive, with our extra circuitry, the PE(1) input on the counters in order to pass the value on It's As to Its Qs When A(Qs on the counters) reach B(Digi-Switchs) in our magnitude comparator.

With this particular circuit We could meet another requirements:
A circuit that count From X to Y and stop.
A circuit that count From X to Y cyclically.
A circuit that count From X to Y and stop and restart again when We push a reset button or a PE button.
Etc.

Always remember to put some logic level to all inputs in all integrated circuits.
Also the X value must be lower then Y value.

I hope this small contribution serve for you.

Note:
By the way, the black boxes with 4 terminal and a number inner are commutators that put on its terminals the binary number on they.

regards
at your service