I'm using the 4516 IC to make a binary counter circuit and I'm trying to limit the outset and the end.
Succeed in limiting the last counting number but have no clue how to limit the outset, it means that I don't know how to define from what number it will start to counte.
For example, I want that counter to start counting from 5 and complete the counting operation after it arrives to 13.
The limitation of the last number has been done by the 4082 IC while I don't know how to do the limitation of the outset.
Can you help me please?
Thanks a lot in advanced.
besides that, there's a terminal count pin in this IC and I can't understand it's purpose.
I assume Englishnis not your first language because the word outset is the wrong word. Do you mean initial count. That is you want the counter to start at 5 and then reset back to 5 when recieving the pulse after it has counted to 13?
That counter is preloadable so you apply the value 5 to the P pins and clock PE when the counter reaches 13.
The only hard part is detecting the 13, that's 1101 in binary so you probably have to set up a few gates to provide a high pulse on that combination. Something line
Q0, Q2 and Q3 to an four-input AND gate.
Q1 to the fourth input via an inverter.
When 13 appears on the counter the AND gate output goes high and loads the counter with 5.
If you want the value 13 to hang around for a full clock period then detect the value 14. 14 is 1110 so all you need is a 3-input AND gate.
Rob
lol, I know that and that's exatly what I did.
But the sole annoying thing in that whole case is the fact that on the first cycle it's initialized from 0 and only from the second cycle it starts from the number I defined.
That's exactly what I don't want!
what I'm trying to do is to initialize the counter to count from a specific number but already on it's first cycle!!!
tried to use a 4 input nor gate but now it starts from 0, than skips to what I defined and so on (gets into a loop).
Again, thanks for your help.
You could use a cap to VCC and resistor to ground to provide a pulse on power up (I think that's the right way around). May have to OR it with the normal pulse.
Rob
What about pin 9 of the 4516 ? Did you build a small reset circuit ? like : +5 V-- 10 K -pin 9 -- 10 uF --GND It work like, when you power up, the cap will be short and recharge, that will provide a LOW reset signal. <--- Opps... the 4516 need a HIGH to reset, so connect the reset signal to a 7404 / 7414 <--NOT gate.
That's pretty much what I was suggesting except if you run the pulse to PE you start at 5. I think if you swap the components around you'll get the high pulse (long time since I've done such a thing). Then diode-OR it with the existing 13 load pulse.
Rob
I get it Graynomad, you mean the "Preset Enable" pin 1 - HIGH to load the data in. ( I download the datasheet at CD4516 Datasheet pdf - CMOS PRESETTABLE UP/DOWN COUNTERS - Texas Instruments It also include a timing diagram. I hope the OP know how to read a datasheet. And yes, it will work by using a reset circuit with a NOT gate to get a HIGH at power-up. And you also need a OR gate and AND gate for the data out reach the desired count digit.