Need your help with 75LS163 counter

Need your help with 74LS163 counter

Hi

My task is to create a counter which counts from 0 to 15 using two 74LS163 and a 74LS00. Decade counting should be used. The first 74LS163 should count ones and the other one tens. And the value should be shown using 8 LEDs.

I have tried doing this coupling tens of different ways but I can't get it working. I have to make this right tomorrow or I will get an F. I can't ask my teacher because he isn't available. So, you are my only hope.


Please, help me.

Re: Need your help with 74LS163 counter

Anunnaki said:

Hi

My task is to create a counter which counts from 0 to 15 using two 74LS163 and a 74LS00. Decade counting should be used. The first 74LS163 should count ones and the other one tens. And the value should be shown using 8 LEDs.

I have tried doing this coupling tens of different ways but I can't get it working. I have to make this right tomorrow or I will get an F. I can't ask my teacher because he isn't available. So, you are my only hope.


Please, help me.

Click to expand...

Here is a schematic for your problem,
with my best regards

'LS163 are up counters with a preset in and Carry Out (CO=1 for out=1111)

Inverting the outputs makes them down counters.
Another way to implement is to make use of these.


To convert the hex counters to decimal you have to preload 6 and count up to 15 then preload again.

when output is 15 or 1111 (CO=1) then preload and recycle

But you don't have to invert the outputs. Just invert the logic of the LED's so Output low = ON to mean 1 thus tie all the Anodes to +5 and drive each LED low with a 330R resistor to each of the 5 Q outputs for 10mA, which the LS TTL can drive in the low state easily.

So all you have are 8 jumpers for preset input = $E6h or 1110 0110 to count 16 times or from 15 to 0 0 and recycle.

Only one NAND gate input from both RCO out signals going to _Load=0 on both chips.
En T and P are both enabled high.

So you have 2 counters and 1 NAND solution with 8 or 5 LEDs to showing the 16 stage count but using Binary Coded Decimal (BCD) mode display. ( but top 3 LED's wont change in a 0 to 15 count.)