## How it works

This design executes binary operations on two octal numbers encoded in an 8-bit instruction and outputs the result to the 7-segment display.
The instruction is made up of 8 total bits.  

Bits 0 and 1 make up the operation code. Operations are according to the following table.
| Bit 0 | Bit 1 | Operation |
| -------- | ------- | ------- |
| 0 | 0 | ADD |
| 0 | 1 | OR |
| 1 | 0 | AND |
| 1 | 1 | XOR |

Bits 2, 3, and 4 make up operand A. Bit 2 is MSB and bit 4 is LSB.

Bits 5, 6, and 7 make up operand B. Bit 5 is MSB and bit 7 is LSB.

A full operation would be decoded like this
|Bit|0|1|2|3|4|5|6|7|
|---|---|---|---|---|---|---|---|---|
|Decoded|OP1|OP2|A(MSB)|A|A(LSB)|B(MSB)|B|B(LSB)|

## How to test

1. Craft a instruction following the above decoding table. 
2. Enter the instruction on the TT08 PCB's input pin dip switches.
3. View the result on the 7 segment display

   Note: An overflow condition during an add operation will illumniate the 7 segment display's DP.

Examples:
- 0 0 1 0 0 0 0 1 -> ADD 4, 1 -> Displays 5 on 7-Segment Display
- 1 1 1 0 0 1 0 1 -> XOR 4, 5 -> Displays 1 on 7-Segment Display
- 1 0 1 0 0 1 0 1 -> AND 4, 5 -> Displays 4 on 7-Segment Display
- 0 1 1 1 0 1 0 1 -> OR  6, 5 -> Displays 7 on 7-Segment Display
- 0 0 1 0 1 1 1 0 -> ADD 5, 6 -> 7-Segment Display DP illuminated indicating overflow condition

## External hardware

The only external hardware required is the 7 segment display provided by the tt08 PCB.