The DM74LS circuit is a synchronous up/down 4-bit binary counter. Synchronous operation is provided by hav- ing all flip-flops clocked simultaneously. 74LS, 74LS Datasheet, 74LS Binary Up/Down Counter Datasheet, buy 74LS D1, 1 •, 16, Vcc. Q1, 2, 15, D0. Q0, 3, 14, MR. CPD, 4, 13, TCD. CPU, 5, 12, TCU. Q2, 6, 11, PL. Q3, 7, 10, D2. GND, 8, 9, D3.
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Use the 74LS to create a Binary up counter. Test and simulate the circuit and verify it works as expected.
After you have made the circuit modify the circuit to count from E. As we learned the has a input called a load and it is loaded with a binary count from the ABCD Inputs. Every time the load gets a 1 it restarts the count at the number that it was given from ABCD.
A disadvantage about the IC is that it only counts up cause u cant change the parts in the inside of the IC. This is the 2-to-9 Binary Up Counter. The way it works is pretty simple. This will make the count restart at 2. To make the count end at 9 I had to place 2 inverters on Q1 and Q2, this made the maximum count be This is the video of the 2-to-9 Binary Up Counter.
It works as expected and makes the counter restart at 2 and restart at 9. The probes show the binary count that go into the HEX Display. It has been bread boarded based on the Multisim design.
Please note that I made a mistake in the video and said the circuit uses a but it actually uses a 74LS IC. This is the 4-to Binary Up Counter that I had to make by modifying the counter. It was actually very easy to modify the count once I got the concept of the MSI counter.
This is the 4-to Binary Up Counter Video. It works according to the design and the probes show the binary count that goes into the HEX display. What are the advantages of implementing a synchronous counter with the 74LS integrated circuit versus using discrete flip-flops and gates?
An advantage of using the 74LS IC over using discrete flip flops and gates is that every thing is dramatically simplified. Are there any disadvantages to using the 74LS integrated circuit? The biggest disadvantage of the 74LS is that it can only count up as I stated above. This is cause it only has a clock that counts up and since the MSI chip is synchronous you can not make it count down.
This gives us the binary number of so the count will start at 1. The thing that makes it so much better than the is that the chip has the capacity to count both up and down.
application | Electronics Forum (Circuits, Projects and Microcontrollers)
The reason it can count is that the Chip has a Up and Down input and depending on which input u put it, is how the clock will count. But as we learned from the lesson the 74LS has a Asynchronous load which means that when it counts down it adds a number so instead of having the count restarts at 5 it restarts at 6.
It works as expected and the probes show the binary count that is fed into the HEX display. The first thing we had to modify from the previous counter was to wire the clock to the up count input of the 74LS To make the number end at 13 we had to change the Q outputs.
As I stated above the Asynchronous load will delay the pulse by one so I put an inverter on Q0. The Asynchronous load subtracts a number which makes the maximum count This is the video of the 6-to Binary Up Counter.
It works according to what we learned and the probes show the binary count that are going into the HEX display. The biggest advantage of the 74LS is that it has the ability to count both up and down unlike the 74LS that can only count up. The 74LS is obviously the best choice cause its flexibility. What is the difference between a synchronous load input i. Their is a big difference between a synchronous and asynchronous load inputs.
For Example on the 6-to up counter you see the inverter on Q0 and you would calculate the maximum count would be on 14 E but since the pulse goes through the asynchronous input and it is counting up, it subtracts a 1 from 14 and this is why the count ends at Analyze the counter shown below to determine the counters lower and upper count limit. Explain how you know this?
74LS193 IC – Binary Up/Down Counter with Clear IC (74193 IC)
A and D are wired to VCC and B and C are wired to 0 and this give us the binary number which means the count will jc at 9. Q0,Q1,2 and Q3 are all inverted so the count would restart at 0 but since it goes through a asynchronous load and it is counting down you must add a 1 so the count will restart at 1.
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