Latest revision as of 14:50, 20 February 2012

--D. Thiebaut 14:38, 20 February 2012 (EST)

Part 1

Build an RS flipflop with NAND gates, as you did in class on Monday. Be careful, the pinout for the NOR gate is not the same as for the NAND gate, so you cannot just swap the two circuits.
Energize the R and S inputs and transcribe the behavior of the flipflop in a timing diagram.

Build another RS flipflop with XOR gates (74LS86). This time you can swap the NAND for the XOR circuit.
Similarly, draw the timing diagram that illustrates the behavior of the flipflop.

Capture the behavior of the NAND RS flipflop when both R and S are connected to the Test-Point 1 and Test-Point 2 of the HP test board. Make sure you connect the GND of the board to the GND of the kit.

Capture the behavior of the NOR RS flipflop when both R and S are connected to the Test-Point 1 and Test-Point 2 of the HP test board. Same comment about the GND signals.

Edit the capture you made (either draw it or edit the graphic file captured on your USB stick) and indicate which part of the timing diagram corresponds to the flipflop being
- in "memory" state,
- in "store 1" state,
- in "store 0" state, and
- in the "forbidden state."

@@ Line 4: / Line 4: @@
 =Part 1=
-* Build an RS flipflop with NAND gates, as you did in class on Monday.  Be careful, you cannot
+==NAND RS Flip-Flop==
+* Build an RS flipflop with NAND gates, as you did in class on Monday.  Be careful, the pinout for the NOR gate is not the same as for the NAND gate, so you cannot just swap the two circuits.
 * Energize the R and S inputs and transcribe the behavior of the flipflop in a timing diagram.
-* Build another RS flipflop with NAND gates.
+==XOR RS Flip-Flop==
+* Build another RS flipflop with XOR gates (74LS86).  This time you can swap the NAND for the XOR circuit.
 * Similarly, draw the timing diagram that illustrates the behavior of the flipflop.