Figure $4\mathrm{.}1$

The light display has two sequences and it will always begin with Sequence $1$ which consists

of all threes lights, followed by Red and Green lights only, with their states pre$-$defined as

$111$ and $011$ respectively. Sequence $1$ will toggle between the two states until the switch

button has been pressed which will change the display to sequence $2.$

Sequence $2$ will always start with a pre$-$defined state $101$ with Blue and Green lights only,

followed by a subsequent state of $110$ with Blue and Red lights. Again, sequence $2$ will

toggle between the two states until the switch button has been pressed which will return the

light display to the start of sequence $1.$

Your design should include three edge triggered D flip$-$flops, with each of the light

components controlled by one D flip$-$flop. Assume that the light display will be run as an

infinite loop as described above until it is turned off. Assumptions on don't cares will not be

suitable in this case. Your answer should include the following:

a$)$ A State Diagram for the light unit. Your state machine should include an initial state of

$\text{'}000\text{'}$ and the light display should always begin with sequence $1.$

$[6$ marks$]$