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Introduction to Logic Analyzers Lab
Procedure:
1. Design a digital sequence generator using an electronically programmable read
only memory (EPROM) device such as an Intel 2716
3. Verify the circuit operation using the logic analyzer as follows:
a) Analyze all EPROM output pins as well as the output pins of all other devices used. The clock pin should be the
first waveform viewed and the sequence generator output waveform the last signal viewed
b) All squarewave waveforms should be properly labeled and documented in your report
c) The logic analyzer should be triggered to start at the beginning of the sequence
d) A legible, readable hardcopy of the digital waveforms should be made
e) Measure the width of the clock pulse, sequence output pulse, and three other pulses. Record the values of the
pulse widths and make hard copies of the clock and sequence output pulse widths showing cursors
4. Demonstrate the circuit operation
5. For the laboratory write-up, turn in the following: The circuit design, the EPROM Program, all documentation
and hard copies of the logic analyzer waveforms
Conclusions and Discoveries:
For the given experiment we were to examine the characteristics of an electronically programmable read-only
memory, EPROM device, discover how to sequentially connect the eprom to external devices, and make timing
measurements using a logic analyzer. An EPROM is simply a collection of internal registers with each register
having an address assigned to them. Therefore, information can be stored in the device in Hexadecimal form
in each register and assigned an address so the data can be recalled at a later time.
With the use of the EPROM, we designed a digital sequence generator with the following characteristics:
1. A single input line
2. One clock signal (timing sync signal)
3. A signal output line
4. A 32bit serial output sequence, self repeating
The design involved connecting the EPROM to two HEX quadruple D-Type Flip-Flops and feeding the outputs of
several flip flops back into the inputs of the EPROM. This allowed for the address lines to shift to the
next memory location. A given input sequence was specified, converted into HEX and programmed into the
EPROM. Once the EPROM circuit was constructed, data measurements were gathered using the logic analyzer.
Overall, the circuit performed within the expected operating parameters. However, an error occurred with
the quadruple d-type flip-flop in using the forth flipflop which created an output error. Therefore, the
circuit design was constructed with the concept of only using three of the four flip-flops in the integrated
circuit. This quickly solved the problem of output errors that were discovered. Although, the initial error
was never narrowed down to the overall cause of the failure, but a wiring error seemed to be a possible
factor. In closing, the given output data was measured exactly to the data inputted to the device as expected,
resulting in a functioning digital sequence generator.
Electrical Engineering lab key words: Logic Analyzer, Digital Circuit, Digital Logic, Digital Systems
experiments, hand calculations, computer simulations, theory, hardware components and instrumentation,
Karnaugh Maps, truth tables, Boolean expression, ORCAD, PLD design, ASM Chart, state assignment, EPROM,
K-Maps, logic gates, logic analysis, clocking, digital fundamentals, decimal, binary, hexadecimal,
conversions, number systems, arithmetic operations, BCD code, parity bit, LSB, least significant bit,
Boolean algebra, simplification theorems, SOP or POS, decoders and multiplexers, flip-flops,
sequential circuits, PLAs, ROMs, LSI devices.
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