Sixty Second Timer
Project Description
The goal for this project was to create a sixty second timer that counts from 00 to 59. The design has two inputs (clock and reset) and two output displays. The first one counts from 0-5 and the second counts from 0-9. When the timer reaches sixty, it resets at zero and starts counting again.
PLD Circuit
This project is similar to the other project because there are two inputs and two output displays. This project is different because it has J/K flip-flops while in the other project we used regular flip-flops. This project we used the 74LS163 MSI counter which detects what is displayed, but in the other project we used the 74LS193 which detects the number after the one displayed. The other difference is how the other one needed a switch to reset the count, while in this project it starts the count over again once it reaches 59 seconds. Other than these differences and the numbers the displays are counting to, the projects are similar.
Conclusions
Synchronous vs. Asynchronous Circuits
The difference between asynchronous and synchronous is that synchronous counters all read the same clock. In asynchronous, each following flip-flop is clocked by the previous flip-flop except the first which is the only one connected to the clock. Being connected to the same clock results in synchronous circuits being faster and more efficient than asynchronous, having no ripple effect or delay. The set back of synchronous counters is that they require more logic, so it yields a higher cost.
'163 vs. '193
'163 and '193 differ in two ways. The first is that '163 only has the ability to count up, where '193 can count up or down depending on the purpose. Secondly '163 shows the number that it detected by load before resetting, where '193 will never show the number before detected by load and resets before it can ever show it.
Process
To design this circuit, I created it in two parts. To start off, I took the template from the DMV display project and modified it. For the tens place, we had to count 0-5 using J/K flip-flops. I created this design implementing three J/K flip-flops setting the upper limit at binary 110 (which is equal to 6) so that the tens place can count to 5. Next I created the ones place with a 74LS163 gate. Since it must always reset to 0, I set the lower limit to 0. I set the upper limit to 9 by setting load to binary 1001 (9) and put my clock into CLK. The upper limit is 9 because for the 74LS163 gate you detect what you want to see. Next I connected the tens and ones to each other by taking the load from the ones and putting it into the clock in the first flip-flop for the tens. This is so when the ones jumps from 9-0, the tens digit will jump up by one. I then implemented the reset switch which I connected to the clears of both figures. After all of these steps, I tested my design by looking at the LEDS to make sure they displayed the correct count (00-59). Once I made sure the right numbers were displayed, I transferred my design to the breadboard to watch it display the numbers on there. My design ended up displaying the correct count and resetting back to 00 once it reached 59.
Classmates Circuits
My circuit was very similar to all of my classmates designed circuits. We all had the same ideas when designing to make it the simplest version. In the end, they all turned out successful with the most logical designs.
The difference between asynchronous and synchronous is that synchronous counters all read the same clock. In asynchronous, each following flip-flop is clocked by the previous flip-flop except the first which is the only one connected to the clock. Being connected to the same clock results in synchronous circuits being faster and more efficient than asynchronous, having no ripple effect or delay. The set back of synchronous counters is that they require more logic, so it yields a higher cost.
'163 vs. '193
'163 and '193 differ in two ways. The first is that '163 only has the ability to count up, where '193 can count up or down depending on the purpose. Secondly '163 shows the number that it detected by load before resetting, where '193 will never show the number before detected by load and resets before it can ever show it.
Process
To design this circuit, I created it in two parts. To start off, I took the template from the DMV display project and modified it. For the tens place, we had to count 0-5 using J/K flip-flops. I created this design implementing three J/K flip-flops setting the upper limit at binary 110 (which is equal to 6) so that the tens place can count to 5. Next I created the ones place with a 74LS163 gate. Since it must always reset to 0, I set the lower limit to 0. I set the upper limit to 9 by setting load to binary 1001 (9) and put my clock into CLK. The upper limit is 9 because for the 74LS163 gate you detect what you want to see. Next I connected the tens and ones to each other by taking the load from the ones and putting it into the clock in the first flip-flop for the tens. This is so when the ones jumps from 9-0, the tens digit will jump up by one. I then implemented the reset switch which I connected to the clears of both figures. After all of these steps, I tested my design by looking at the LEDS to make sure they displayed the correct count (00-59). Once I made sure the right numbers were displayed, I transferred my design to the breadboard to watch it display the numbers on there. My design ended up displaying the correct count and resetting back to 00 once it reached 59.
Classmates Circuits
My circuit was very similar to all of my classmates designed circuits. We all had the same ideas when designing to make it the simplest version. In the end, they all turned out successful with the most logical designs.