I have this assignment and I am not sure how to do this and a simple google wouldn't help me. Also not exactly sure what to search for.
But I'm creating a clock / watch that contains hours, minutes and seconds. And the bitmask I'm given to use is:
0000 0000 mask1
hhhh mmmm
0000 0000 mask2
mmss ssss
What I understood so far is that the amount of Hour bits is the reason to fit 12 options from 0 -> 11. And the 6 bits for minutes and seconds for 0 -> 59.
For hours I kindof went in the dark creating 12 seperate bitmasks for each possible hour. After I finished I realized I had to do this for minutes and seconds as well which would be 120 lines of unneccessary code.
This is what I did:
TIME_11_HOUR = 240, //1111
TIME_10_HOUR = 224, //1110
TIME_9_HOUR = 192, //1100
TIME_8_HOUR = 160, //1010
TIME_7_HOUR = 144, //1001
TIME_6_HOUR = 112, //0111
TIME_5_HOUR = 96, //0110
TIME_4_HOUR = 80, //0101
TIME_3_HOUR = 64, //0100
TIME_2_HOUR = 48, //0011
TIME_1_HOUR = 32, //0010
TIME_0_HOUR = 16 //0001 0000
I believe the solution has to do with bit shifting but im not really sure how to do that.
Could anyone give me an example to change 0001 (0 hour) to 1010 (8 hour) so I can implement this in my code and figure it out on my own.
assuming all values are within range and using unsigned types...
to unencode
hour = (encodedtime & 0xf000) >> 12;
minute = (encodedtime & 0xfc0) >> 6;
second = encodedtime & 0x3f;
to encode
encodedtime = (hour << 12) | (minute << 6) | second;