Create two new files src$/$spi$.$c and include$/$spi$.$h$.$

TASK:

$1.$ In "spi.c$",$ declare and implement a function "spi$\_$init" that

will initialise SPI$0$ in unbuffered mode, such that data can

be written to the shift register that controls the $7-$segment

display.

This function should also enable the SPI interrupt via the

IE bit in INTCTRL.

$2.$ Declare and implement the function spi$\_$write$($uint$8\_$t b$)$

which will write the byte b out via the SPI interface.

$3.$ Declare and implement an ISR that handles the SPI interrupt,

and also creates a rising edge on the DISP LATCH net.

You will need to add some code to spi$\_$init$()$ to enable the

required pins as outputs.

Declare prototypes for these functions in "spi.h$"$ and include

"spi.h$"$ at the top of this file.

Once this exercise is complete, uncomment the lines below. The

$7-$segment display should be blank after this code executes.