hi,
Downloaded those files, ok.
Will post tomorrow.
E

ok, thank you very much!!!

 

hi p3,
Look at these marked up drawings, your Bread Board layout is almost correct, but has one PL line error and is not wired according to your diagram.

If you wire the board as per the circuit it should operate as expected.
Get it working as shown, then consider how you would add those extra push buttons.
Added the IC pin numbers.
E

 

hi p3,
Look at these marked up drawings, your Bread Board layout is almost correct, but has one PL line error and is not wired according to your diagram.

If you wire the board as per the circuit it should operate as expected.
Get it working as shown, then consider how you would add those extra push buttons.
Added the IC pin numbers.
E

i think that i misunderstanded your circuit, because i saw the /PL and the Preset going in to pl so i though "oh i have to connect the Preset at both /PL", where exactly the Preset and both /PL are connected ?

 

hi p3,
Note the 'pl' ident labels, shows they are linked.

E

 

hi p3,
Note the 'pl' ident labels, shows they are linked.

E

as i can understand preset and both /PL are wired at the push button that controls the clock.

 

hi,
Yes,
Let me know when you have it working.
E

 

hi,
Yes,
Let me know when you have it working.
E

i did the connection like your circuit, but the problem now is that i can't control the digits using the buttons at CPU, also i needed to set p0,p1,p2,p3 at low, otherwise the display wouldn't turn on

 

i did the connection like your circuit, but the problem now is that i can't control the digits using the buttons at CPU, also i needed to set p0,p1,p2,p3 at low, otherwise the display wouldn't turn on

hi,

When you pressed the Start button, did the circuit count Down as expected.?

I did say that you would have to modify the circuit if you wish to control the individual Digits.

What are ' p0,p1,p2,p3' I do not see them on the drawing.?

E

 

hi,

When you pressed the Start button, did the circuit count Down as expected.?

I did say that you would have to modify the circuit if you wish to control the individual Digits.

What are ' p0,p1,p2,p3' I do not see them on the drawing.?

E

p0-15 and p3-9 are connected in VCC and p1-1 and p2-10 are connected in GND.

 

hi,
From your drawing I thought you had already done that.?

Of course you must have '1001' decimal 9 on the 192 Parallel inputs.

 

hi,
From your drawing I thought you had already done that.?

Of course you must have '1001' decimal 9 on the 192 Parallel inputs.



View attachment 238804

yes, i did that, the problem that i found is if i connected the /PL pin of both IC at the push button, it will lose that automatic part, and i'm still having problem with the counter stoping at 99 with everything wired correctly

 

So when you press the Start button does it show '99' and then start counting down to '00' and then '99'.?

What are you using to generate the clocking pulse that goes into the AND gate.?

E

 

So when you press the Start button does it show '99' and then start counting down to '00' and then '99'.?

What are you using to generate the clocking pulse that goes into the AND gate.?

E

in my actual circuit yes, i'm using the a timer and the Q of 74ls74 for the AND input gate.

 

hi,
OK.
Is this an actual circuit you are building or is it a simulation.?
What is the timer you are using.?

E

 

hi,
OK.
Is this an actual circuit you are building or is it a simulation.?
What is the timer you are using.?

E

it's a simulation, there is a thing called "temporizador" in the program that i sent you yesterday that works like a timer.

 

As you can see it works OK in my LTSpice simulator.
If your connections are the same mine in the circuit it suggests a difference in the simulators operation.??

What is the name of your simulator.?

 

As you can see it works OK in my LTSpice simulator.
If your connections are the same mine in the circuit it suggests a difference in the simulators operation.??

What is the name of your simulator.?

it's the one that i sent you yesterday, where you painted with a green line the /PL wire

 

i was checking in some other forum that if i don't reset or clear the 74ls192 the count will keep counting, how can i do that ?

 

hi,
How can it keep counting if the AND gate has been disabled by the 7474 being reset by the TCD going Low..??
ie: no clock input, no count.
E

 

hi,
How can it keep counting if the AND gate has been disabled by the 7474 being reset by the TCD going Low..??
ie: no clock input, no count.
E

oh, i'm so sorry xD the problem was exactly what you just said, i was using a NAND gate instead of an AND, everything is working now, thank you very much my friend, you helped me alot!!