Project Overview
In this project we had to create a circuit on multi-sim that could count from 0 to 80 using D flip-flop chips and a 74l293 MSI counter. This circuit also had to be reset with a switch and would stop at 80 seconds on its own. The counter and chip also had to be able count together on the same clock.
PLD vs Design mode
PLD mode uploads the circuit created directly into the board and is connected to the pins 1-48 on the chip. PLD contains less wires when creating a circuit from design mode, for example you would need to connect the chip to power and ground while also connecting buttons on the bread board to certain inputs and outputs on the circuit,(1-48). Design mode is the "test or prototype" of the circuit in which we can design and test simulations before having to recreate them on the Breadboard. The outputs and inputs of design mode are connected to LEDs or digit displays.
Conclusion
SSI are small scale integration circuits which use the basic AOI chips that can only go up to ten or lower. While MSI are medium scale integration uses chips that are greater then 10 but less then 100. For my deli counter i used the 74LS93N chip for my "ones" place counting from 0-9. I got this to count from 0-9 by connecting my most significant bit "D" and "B" bit to the 74L220N gate while the other two inputs are connected through inverters telling them to be zero. For my 0-8 display in the "tens place" i used D Flip-Flops. To get this to count to 8 i connected the 74LS20N to the most significant bit "Q" on the far right while connecting the others to "not Q". I connected the circuits together by connecting their clocks together allowing them to count at the same time. Then to apply my reset switch i connected a NAND gate to the clock of my D Flip-Flops and to the output of my 74ls93N chip. This NAND gate represented an and gate we used in a previous classwork that controlled the reset switch. To tell my circuit to stop exactly 80, i connected the output of an AND gate to the "INA" on the 74LS93N chip. I connected the inputs to my clock and to the most significant bit in my D Flip-Flops, however for the most significant the wire passed through a inverter. This told the displays to stop because in a previous classwork to pause the display we flipped a switch to ground making it a 0 while the other input was a 1 and pausing the entire circuit, so recreate this i connected the one input to the clock as a 1, and the other to my most significant bit through an inverter making it a zero. My design did have a ripple effect because when changing through each digit it would flicker meaning it had a delay. My classmates circuits were different from mine, since there were many possible ways for this circuit to be created, somethings people did differently were using a NAND gate to make it stop instead of using an and and inverter gate.
"I hope all of this made sense Mrs.Z"
"I hope all of this made sense Mrs.Z"