Exercise 1 Simple Reaction Controller

Assignment 1

The due date: 11:59pm, Friday, 6th of September 2019.

This assignment is worth 14% of the total course mark.

1. Objective

The purpose of this assignment is to make you familiar with the problems posed by

event-driven systems. As a supplementary task you also need to implement a simple

Graphical User Interface.

2. Specification

Exercise 1 Simple Reaction Controller

Imagine that you have been hired by an electronics company to build the software for

a simple Reaction-Timer game. The reaction timer has two inputs: a coin-slot that

starts the game and a go/stop button that controls it. There is also a display that

indicates to the player what he/she should do next. The machine behaves as follows.

• Initially, the display shows “Insert coin”, and the machine waits for a player to do so.

• When the player inserts a coin, the machine displays “Press GO!” and waits for the

player to do so.

• When the player presses the go/stop button, the machine displays “Wait...” for a

random time between 1.0 and 2.5 seconds. After the random delay expires, the

machine displays a time-value that increments every 10 milliseconds, starting at zero.

The player must now press the go/stop button as soon as possible – the goal of the

game is to show fast reactions! If the player presses the go/stop button during the

random delay period, i.e. the player tries to “guess” when the delay will expire, the

machine aborts the game and immediately demands another coin. To put it simply,

there is no reward for trying to cheat! If the user has not pressed stop after two

seconds, the machine will stop automatically – no living person could be that slow!

• Whether the player has pressed the go/stop button within the two seconds waiting

time period or not, the machine displays the final timer value for three seconds, then

the game is over until another coin is inserted. If the player presses the go/stop button

while the measured reaction time is being displayed, the machine immediately

displays “Insert coin”.

Exercise 2 Enhanced Reaction Controller

After showing the basic reaction timer machine to potential customers, the marketing

department has found that some of them would like to pay more for a deluxe reaction

timer that allows multiple games after payment of a single coin. In this machine, when

a coin is inserted, the player is allowed to play three games. The operating sequence

is very similar to the previous one: insert coin, press the go/stop button, wait random

delay, press the go/stop button, then display the time for three seconds. If the

machine has not yet completed three games, it then displays “Wait...”. Subsequently,

it waits a (new) random delay and proceeds further as in the first game. After

displaying the time for the last game, the machine shows the average time “Average=

t.tt” for five seconds, then the game is over. The enhanced reaction controller

should fulfil the following requirements.

• If after inserting the coin the player fails to press go/stop within ten seconds, the

game is over.

• If the player presses the go/stop button during the waiting period, the game is

aborted, and the average value is not displayed. Once again, no reward for cheating!

• If the player presses the go/stop button while the machine is displaying a reactiontime value, the machine immediately moves on to the next game (or shows the