The AT$90$ lab board is equipped with the DS$1305$ real$-$me clock. The clock can be programmed

through the serial peripheral interface. It is connected by the pins PB$0-3($SS$,$ SCK$,$ MOSI, MISO$)$ and

PE$4($INT$4).$

Objec$$ve: Write a program to realize an advanced alarm clock using SPI. The program should have

the following features:

$1.$ Bu$$on $1$:

$$ Sets the alarm $$me for $15$ seconds from now $($overriding any previously set alarm$).$

$2.$ Bu$$on $2$:

$$ When pressed, the LED strip should flash with a period of $500$ ms$,$ indica$$ng the

system is wai$$ng for user input.

$$ The user must input two integers via the computer$$s keyboard transferred through

UART serial port by Pu$$y as per instruc$$on given in Lab $10.$ These integers represent

seconds.

$$ Once the second integer is entered, the alarm $$me will start $($overriding any

previously set alarm$).$

$3.$ Bu$$on $3$:

$$ Deac$$vates the current alarm.

$4.$ Alarm Ac$$va$$on:

$$ When the alarm $$me is reached, a beeping sound should be heard.

$$ The beeping con$$nues un$$l any of the bu$$ons is pressed $($either deac$$va$$ng the

alarm or se$$ng a new one$).$

Hint: It may pay off to start simple, e$.$g$.,$ by first wri$$ng a program that just displays the $$me in

seconds on the LED strip.

A diagram may help you to structure your thoughts, but it is not required as part of this week$$s lab

submission.