can you tell me what is the "tdnb" i think that is not a common initials in my country? my teacher never mentioned that before, also as i can see that i need the preset and clear to make it start with the push button instead of automatically, so the preset goes at PL in 74ls192 and CLR goes at tdnbhi p3,
This clip from a simulation, shows the method I used for manual Start/Stop, also stop at '00'.
It looks a little complicated, but it uses a Bistable which Clocked On/Off with a push button.
This starts and manually stops the count down.
The Bistable is also Reset by the tdnb, Down count output of the second 74192.
Do you follow OK.?
E
oh, i see, i understand now, i would like to see if possible, but i would like to know if the preset from JK is connect to /PL at 74ls192him
The 74192 datasheet shows an output pin marked as TC/D Terminal Count Down , which means when the Counter reaches Zero this pin goes LOW.
I use the letters tdnb for that pin in my diagram, the B tells me its the 2nd 74192 IC.
OK.?
E
Would you like to see the full LTSpice simulation plot.?
i understand what you did, everything is working like i was expecting but the part of stoping at 00 is not working, it stop at 99, i'm pretty sure that is something related to the D0,D1,D2,D3 ports, but thanks alothi p3,
I don't expect you fully understand the simulation at this stage of your learning, [hopefully one day.] but it is just to show you that your basic circuit works.
Ask if you have query.
E
well, one problem is that i can't connect both MR at each other, because it doesn't let the counter leave the 0, i'm really having a big problem to make it stop at 0, do you have any idea about what can cause that ?hi p3,
I would recommend that you don't use the decoded D0,..D3 outputs as a control method, it will give you problems with timing.
Use the TC/D pin on the last 74192.
E
i didn't connected the two count up in 5V because i need to control them using a push button, and in the small image the ports 9 and 15 are connect at VCC and 1 and 10 are connect at GND in both circuits to make the 9 according to the truth table, i did all connections according to you , but that is a old drawhi,
You have not wired this part as I suggested.
Also the two Count Up clocks should be connected to +5V
You said you wanted a 99 to 00 Down Counter.
E
Also in small image, please show ,ore clearly how the D inputs and the PL are connected.??
i redraw the schematic to show you the connections that i did.i didn't connected the two count up in 5V because i need to control them using a push button,
hi,
What are you going to use these two push buttons for.???
It may mean a change in the circuit design.
E
Where are pin 11's, PL connected.?
if you want i can send you the program that i'm using and the file of my projecti didn't connected the two count up in 5V because i need to control them using a push button,
hi,
What are you going to use these two push buttons for.???
It may mean a change in the circuit design.
E
Where are pin 11's, PL connected.?
i uploaded the program in mega.nz so you can download it, the program is in spanish so i don't know if you will understand what is write in the program https://mega.nz/file/zlM0mbYS#RnN1w2d4DRtcEkkknuAzPNRsrmysWAMYhGn0S4gHHoAhi p3,
I would like that, thank you.
We can then compare notes.
BTW: if you intend using one of the extra push buttons to change the Up Clock input, remember the Down Clock pin MUST be High,
E
by Jake Hertz
by Aaron Carman
by Jeff Child
by Jake Hertz