c++ - Inserting bits into byte -


I was seeing an example reading bits from a byte and the implementation was simple and easy to understand. I was thinking that anyone has a similar example of inserting bits into a byte or byte array, it is easy to understand and also applies like the example below.

There is a byte reading bits: 

  Fixed bit beats 3 (byte b, int offset, ant count) {return (b & gt; & gt; offset ) & Amp; ((1 & lt; c; count;) - 1); }

What I'm trying to do here is my current implementation, I'm a bit confused with bit-masking / transfer etc, so I'm trying to figure out What is an easy way to do that 

  BYTE message [2]; Msg_Id = 3; Msg_Event = 1; Msg_Ready = 2; Message [0] = ((Msg_Event <4) & amp; 0xF0) | (MSS_ID & amp; 0x0F); Message [1] = message_radi & amp; 0x0F; // MsgReady & amp; Unused  
 
 If you are continuously using consecutive constant values ​​like the above example, then you should move bits with these constants Put them in the time of a byte. Otherwise they overlap: In your example,  Msg_Id  is equal to  Msg_Event & amp; Msg_Ready . It can be used 
 
  the message [0] = (1  
 
 (Note that the bits inside a byte are indexed from 0.) The second method will use the powers of constant values ​​of 2: 
   Msg_Id = 4; // equal 1 & lt; & Lt; 2 Msg_Event = 1; // equal 1 & lt; & Lt; 0 Msg_Ready = 2; // equal 1 & lt; & Lt; 1

Note that in your code above, there is no need for masking with 0x0F or 0xF0 : (Msg_Id & amp; 0x0F) == Msg_Id and ((Msg_Event .


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