Coursework 2: 2D Led Array

In this task, we assume that an 8×8 LED array is controlled by 2 words specified in led_array . Each bit in this memory space controls the on/off state of one LED with 1 turns on an LED and 0 turns off an LED. Each byte of the led_array maps to one row of LEDs and the least significant bit of this byte controls the right -most LED of this row. CourseNana.COM

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 0th byte Bit 15 Bit 14 Bit 13 Bit 12 Bit 11 Bit 10 Bit 9 Bit 8 1st byte . . . . . . . Bit 16 2nd byte . . . . . . . Bit 24 3rd byte . . . . . . . Bit 32 4th byte . . . . . . . Bit 40 5th byte . . . . . . . Bit 48 6th byte Bit 63 Bit 62 Bit 61 Bit 60 Bit 59 Bit 58 Bit 57 Bit 56 7th byte CourseNana.COM

One example is shown below. 0x81 is the first byte of led_array, the first bit is 1 and the last bit is also 1, this will turn on the top left and top right LEDs. CourseNana.COM

led_array DCD 0x00000081, 0x81000000 CourseNana.COM

    0th byte
    1st byte
    2nd byte
    3rd byte
    4th byte
    5th byte
    6th byte
    7th byte

If there were issues found in this coursework specification after its initial release, it will be updated and announced on LMO. Task 1: (60%) In this task, we assume that only one LED on the edge of this led array is turned on. Implement the function “spin_single”, which rotates the position of the light -emitting LED clock -wise once. CourseNana.COM

For example, if the original state of led_array is: led_array DCD 0x18666602, 0x00243C3C 0th byte 1st byte 2nd byte 3rd byte 4th byte 5th byte 6th byte 7th byte CourseNana.COM

After calling function “spin_single” once, led_array should become: led_array DCD 0x18666601, 0x00243C3C 0th byte 1st byte 2nd byte 3rd byte 4th byte 5th byte 6th byte 7th byte CourseNana.COM

Calling it once more, led_array should become: led_array DCD 0x18666700, 0x00243C3C 0th byte 1st byte 2nd byte 3rd byte 4th byte 5th byte 6th byte 7th byte CourseNana.COM

Calling it once more, led_array should become: led_array DCD 0x18676600, 0x00243C3C 0th byte 1st byte 2nd byte 3rd byte 4th byte 5th byte 6th byte 7th byte CourseNana.COM

There are 4 important requirements/restrictions on your program: CourseNana.COM

1. Your function should not modify the state of any LEDs in the middle. Only the LEDs on the edge can be changed.
2. You are not allowed to use DCD (or similar assembler directives like DCW or DCB) to declare new memory blocks.
3. Your function must return to its caller when finished.
4. You should not assume a fixed initial position of the light -emitting LED on the edge. It may appear at any position when spin_single is called.

Task 2: (40%) Implement the function called “spin_multi”, which rotates light -emitting LEDs on the edge clock - wise once. There’s no fixed pattern for light -emitting LEDs on the edge. Given the example state of led_array below: CourseNana.COM

    0th byte
    1st byte
    2nd byte
    3rd byte
    4th byte
    5th byte
    6th byte
    7th byte

After calling spin_multi once, it should become: CourseNana.COM

    0th byte
    1st byte
    2nd byte
    3rd byte
    4th byte
    5th byte
    6th byte
    7th byte

Calling spin_multi again, it should become: 0th byte 1st byte 2nd byte 3rd byte 4th byte 5th byte 6th byte 7th byte CourseNana.COM

Just like task 1, There are 4 important requirements/restrictions on your program: CourseNana.COM

1. Your function should not modify the state of any LEDs in the middle. Only the LEDs on the edge can be changed.
2. You are not allowed to use DCD (or similar assembler directives like DCW or DCB ) to declare new memory blocks.
3. Your function must return to its caller when finished.
4. You should not assume a fixed initial position of the light -emitting LED sequences on the edge.