Steps:

Implement the Proteus circuit from Lab$3$ with only one Seven Segment Decoder $(7448$ or $4511).$

Take the chronometer code from Lab$3$ and make changes to it$,$ so that the chronometer can

work with only one Seven Segment Decoder but works fine for all $3$ digit. $($Hint: if you get stuck,

search the concept on google$)$

int ones $=0$;

int tens $=0$;

int hundreds $=0$;

int state $=0$;

void main$()\{$

PCON.OSCF $=1$;

TRISB $=0$x$00$;

PORTB $=0$x$00$;

TRISA $=0$xF$0$;

while$(1)\{$

if$($RA$6\_$bit $==1)\{$

ones $=0$;

tens $=0$;

hundreds $=0$;

$\}$

else if $($RA$5\_$bit $==1)\{$

state $=1-$state;

while$($RA$5\_$bit $==1)\{\}$

$\}$

if$($state $==1)\{$

delay$\_$ms$(100)$;

ones$++$;

if$($ones $==10)\{$

ones $=0$;

tens$++$;

$\}$

if$($tens $==10)\{$

tens $=0$;

hundreds$++$;

PORTA $=$ hundreds;

$\}$

if$($hundreds $==10)\{$

ones $=0$;

tens $=0$;

hundreds $=0$;

PORTA $=$ hundreds;

$\}$

PORTB $=($ones tens;

$\}$

$\}$

$\}$

int ones $=0$;

int tens $=0$;

int hundreds $=0$;

int state $=0$;

int times $=1$;

int i $=0$;

void main$()\{$

PCON.OSCF $=1$;

TRISB $=0$x$00$;

PORTB $=0$x$00$;

TRISA $=0$xF$0$;

while$(1)\{$

if$($RA$6\_$bit $==1)\{$

ones $=0$;

tens $=0$;

hundreds $=0$;

$\}$

else if $($RA$5\_$bit $==1)\{$

state $=1-$state;

while$($RA$5\_$bit $==1)\{\}$

$\}$

if$($state $==1)\{$

for $($i $=0$; i