Exam May 2015, questions PDF

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Summary

Digital Design Exam Paper - Summer 2015...

Description

UWE

Faculty of Environment & Technology

University of the West of England

BRISTOL

Academic Year: Examination Period: Module Leader: Module Code: Module Title: Work Item Title:

Nigel Gunton UFMFE8-30-2 Digital Design Exam2

Duration:

3 Hours

14/15 Summer 2015

Standard Materials required for this examination: Examination Answer Booklets

Yes

Multiple Choice Answer Sheet

No

Type of paper e.g. G3, G14

None

Graph Paper Number of sheets per student

0

Additional materials required for this examination:

Details of additional material None To be collected with Answer Booklet (please delete as appropriate)

No

Details of approved material None To be collected with Answer Booklet (please delete as appropriate)

No

University approved Calculator

Yes

Candidates permitted to keep Examination Question Paper

Yes

Candidates are NOT permitted to turn the page over until the exam starts

UFMFE8-30-2

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1. Laboratory Examination Design Specification The ACME Vending Company manufactures canned drink vending machines. These machines only ever supply one type of drink. The machine will accept 10p, 20p and 50p coins. A drink costs 50p and the machine gives no change. A drink will be dispensed when sufficient money has been inserted and the vend button has been pressed. An ’EMPTY’ light will be illuminated if there are no drinks left. Coins will be automatically rejected by the vending machine if inserted when the ’EMPTY’ light is on. You are required to design and implement a state-machine for the control unit for the vending machine You may assume that: there is an input, or inputs, that identify which coin has been inserted, there is an input that identifies when the machine is empty, there is an input that identifies when the ’vend’ button has been pressed, there is an output that releases the drink. If you make any other assumptions then you must declare them in your exam book. Attempt all parts: ALL FILES MUST BE SAVED IN THE EXAM FOLDER OR SUBFOLDERS. 1) Provide, in your exam booklet, a correctly labelled Algorithmic State Machine (ASM) Diagram that implements a controller for the vending machine. All states must be given meaningful names. Credit will be given for correct use of ASM notation and correct labelling. (15 marks) 2)

Design in your exam_1 directory a controller using behavioural modelling. You should ensure that your code is commented where appropriate. A template has been provided. Credit will be given for your code matching your ASM, correctness of logic and use of VHDL. If you have trouble synthesising your design then ensure that you still attempt part 3) and also indicate the structure of your vector waveform file for part 4) (15 marks)

3)

Describe, in a text f ile, a test strategy for your controller and also indicate the expected results. Save this in the exam folder. Credit will be given for clearly showing your sequence of input stimuli and the expected response of the system. Credit will also be given for an overview of your test strategy. (10 marks)

4)

Run a functional simulation of your model of the controller. Use a waveform vector file that implements the test strategy that you outlined in 3). Ensure that you save the simulation results in an appropriately named file. If you were unable to synthesise your design you should still create an input vector waveform file. Expor t the waveform as (10 marks)

Notes • Waveforms may be expor ted as follows. a) Right-click on the waveform and select

UFMFE8-30-2

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• • • •

b) In the Wave window open the menu and select c) Rename the file to the appropriate name and save it. You may access the help functions of the Altera and Modelsim tools. Drawings, ASM diagrams and any design notes or assumptions made must be entered into the exam book provided. You must use the temporary account ID and login provided. A quar tus project will have already been created for you and will contain a top level VHDL state-machine template and a short simulation file template (in the simulation folder).

UFMFE8-30-2

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