Eight Available sensors

Each hardware sensor provides a $$high$(1)$ or $$low$(0)$ output. The input interface sub$-$system

sets the value of the corresponding global integer variable to the respective value. The decision$/$

control logic sub$-$system will read this integer to take the right decision. It is assumed that this

integer is available for C programming. The i$/$p i$/$f sub$-$system keeps monitoring the sensor

hardware outputs and acts $($changes value of the integer variable$)$ as soon as the sensor output state

changes.

$1.$ DSBF $$ driver seat belt fastened. This sensor indicates whether the driver seat belt is

fastened or not. The sensor hardware provides $$high$$ when the driver's seat belt is

fastened, $$low$$ otherwise. The corresponding integer variable that reflects the physical

states inside the computer and programming world is $$driver$\_$seat$\_$belt$\_$fastened$.$ The i$/$p

i$/$f sub$-$system sets this integer to $1$ when DSBF output is high, and to $0$ when DSBF is low,

and the decision$/$control sub$-$system code reads$/$uses it$.$

$2.$ ER $$ engine running. This sensor indicates whether engine is running or not. It provides

$$true$$ when engine is running, false otherwise. The corresponding integer variable to read

and use is $$engine$\_$running$.$

$3.$ DC$-$ doors closed. Indicates whether all doors are closed or not. The corresponding integer

is $$doors$\_$closed$.$

$4.$ DLC $$ door lock lever. This indicates whether the door lock lever is closed or not. To close

the electronic door locks the driver must close this door lock lever. When the car$$s

computer finds that door lock lever is closed it checks all other variables to assess the

situation and finally decides whether to activate the electronic door locks to lock the doors

or not. For example, if the car keys are still inside but the driver is not on seat $($has gone out

of car$)$ then the doors should never be locked even though the driver has closed the door

lock lever.

$5.$ DOS $$ driver on seat. This sensor indicates whether a driver is present. This sensor

provides logical $$high$(1)$ as output when a person is sitting on the driver$$s seat and $$low$$

$(0)$ if he is not on the seat.

$6.$ KIC $$ key in car. Indicates that the keys are still inside the keyhole, the corresponding

integer variable is $$key$\_$in$\_$car$.$

$7.$ BP $$ brake pedal. This indicates that the brake pedal is pressed by the driver.

$8.$ CM $$ car moving. This sensor indicates the car is moving and at least one of its wheels are

turning. The corresponding integer variable $$car$\_$moving$$ has value $1$ when the car is

moving and has value $0$ if the car is not moving.

Three Available actuators

$1.$ BELL $-$ A beeper$/$chime that sounds$/$plays to alert the driver of any abnormal$/$hazardous

situation $($as found in your car$).$ A global integer variable named $$bell$$ is provided in the

computer, if your code that implements the decision$/$control sub$-$system sets this variable to

$1,$ then the output interface sub$-$system will read this value and turn on the voltage on the

electrical wire that feeds the beeper$/$chime$.$ As a result, the beeper$/$chime will start beeping.

The beeper will stop when the decision$/$control subsystem code sets the value of $$bell$$ to $0,$

because then the o$/$p i$/$f will turn down the electrical voltage feeding the beeper hence it

will stop. The o$/$p i$/$f keeps on monitoring the integer variable and acts $($change the voltage$)$

when the integer changes its value.

$2.$ DLA $$ door lock actuator. This actuator locks the doors. A corresponding global integer

variable named $$door$\_$lock$$ is provided in the computer, if you set this integer to $1$ all the

doors are locked, it unlocks all doors when you set the value of $$door$\_$lock$$ to $0.$

$3.$ BA $$ brake actuator. This actuator will activate the disk brakes in each of the four wheels if

the global integer variable $$brake$$ is set to $1.$ The brake will be released when this variable

is set to $0$ by the code that implements the decision$/$control logic sub$-$system.

Six Requirements

$1.$ The BELL should chime$/$sound when the driver starts the engine without fastening his

seatbelt.

$2.$ The BELL should sound when the driver starts the engine without closing all the doors.

$3.$ The BELL should be off as soon as the conditions change to normal, i$.$e$.$ the two cases

above do not occur.

$4.$ The doors should not lock when the driver has got out of the car, but the keys are still

inside the engine, even though the driver has closed the door lock lever.

$5.$ If the driver is on the seat and requests the doors to be locked $($turn on the door lock lever$),$

the doors must lock.

$6.$ The brake should be engaged when the driver presses the brake pedal. Brakes should

disengage when the brake pedal is released. The brake should engage only when the car is

moving, when the car is stationary the brake should not unnecessarily engage to reduce

mechanical wear and tear of the brake$$s hydraulic system.

Activities to do$-(7$ points for a$,6$ points for b$,$ and $12$ points for c & d together$)$

a$)$ Create $3$ truth tables, one fo