CS322 Computer Architecture 
HW#1: Logic Probe Due:Jan.25/2005

Parts list

(2) Patch Boards
Wire Stripper
IC Extractor
Battery Holder
(2) 7 Segment Readouts
Dip Switch
SPDT Push Button
(10) red LEDs
(10) 330 ohm resistors
(4) 1K resistors
470K resistor
1M resistor
10M resistor
1 uf capacitor
(2)spools of #22 wire(solid)
(4)74LS00 Quad Nand gates
(2)7402 Quad Nor gates
(2)74LS04 Hex Inverter
(2)74LS08 Quad And gates
74LS32 Quad Or gate
74LS42 4 to 10 decoder
(2)74LS48(common cathode) or 74LS47(common anode)
(2)74LS74 Dual D flip-flops
(2)74LS75 4 bit latch
(2)74LS73 or 74LS76 Dual J-K flip-flops
74LS83 4 Bit Adder
74LS85 4 Bit Comparator
74LS86 Quad Xor gates
74LS90 4 bit counter
74LS93 4 bit counter
74LS151 8 to 1 mux
74LS153 dual 4 to 1 mux
74LS157 quad 2 to 1 mux
74LS163 4 bit(synchronous) counter (2)74LS189 16 x 4 bit RAM
(2)74LS194 4 bit shift register
555 timer

Before you can get started you will have to buy 4 D batteries. You might also want to have a long-nose pliers(to straighten pins and insert wires).

Experiment #1

  1. Set up your patch board so that one row along the top of the board is a +5 volt bus(red battery wire) and another is a ground bus(black battery wire).
  2. Test your connections by wiring a red LED in series with a 330 ohm resistor and connecting one side of the circuit to +5v and the other side to ground. If the LED doesn't light, reverse the connections. Never connect a LED to +5 volts without a current-limiting resistor in series or you will burn out the LED. You can leave this circuit connected and use a wire connected to the anode(+5 v side) of the LED as a logic probe.
  3. Look up the pin diagram of a 74LS00 IC in your IC packet and use it to implement the logic expression (A and (not B)) or ((not A) and B)(the exclusive or of A and B).Use the dip switch for the A and B inputs, and use your logic probe as the output. Make sure you plug the IC into the patch board with the locating notch on the left. Then the pins are numbered from 1 to 7 from left to right along the bottom of the chip, and from 8 to 14 from right to left along the top of the chip. About the only way you can burn out an IC is by plugging it in backwards, i.e., with the +5 volt and ground connections reversed. You will probably discover your mistake soon enough, since the IC will become hot enough to burn your fingers. You may have to use the logic probe to troubleshoot the individual NAND gates in your circuit. Hand in a wiring diagram of your circuit and a truth table.
  4. Use De-Morgan's theorems to represent 2 input AND, OR, NOR, XOR, and XNOR functions with 2 input NAND gates. Don't wire up these circuits.


Hand in wiring diagrams for all your circuits(use Logisim to generate these).

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