Useful Functions

1. reading and writing to the codec.
2. reading from the sram - 16b
3. reading from the sram - 18b
4. writing to the sram - 16b
5. writing to the sram - 18b
6. sampling the switch to change functions - no initialization
7. sampling the switch to change functions - with initialization
8. initialization routine
9. 16b signed x 16b signed to (16b or 32b) signed number
10. 16b signed x 8b unsigned to (16b or 24b) signed number
11. 16b signed x 16b unsigned to (16b or 32b) signed number
12. two's complement of 16b number
13. two's complement of 24b number
14. adding signed numbers of different lengths