Utilities

Function to read bits in a byte buffer.

This function is used to extract up bit values from an array. Up to eight bit values can be extracted in one step.

Parameters:

ucByteBuf	A buffer where the bit values are stored.
usBitOffset	The starting address of the bits to set. The first bit has the offset 0.
ucNBits	Number of bits to modify. The value must always be smaller than 8.

 UCHAR ucBits[2] = {0, 0};
 UCHAR ucResult;

 // Extract the bits 3 - 10.
 ucResult = xMBUtilGetBits( ucBits, 3, 8 );

Definition at line 86 of file mbutils.cpp.

Function to set bits in a byte buffer.

This function allows the efficient use of an array to implement bitfields. The array used for storing the bits must always be a multiple of two bytes. Up to eight bits can be set or cleared in one operation.

Parameters:

ucByteBuf	A buffer where the bit values are stored. Must be a multiple of 2 bytes. No length checking is performed and if usBitOffset / 8 is greater than the size of the buffer memory contents is overwritten.
usBitOffset	The starting address of the bits to set. The first bit has the offset 0.
ucNBits	Number of bits to modify. The value must always be smaller than 8.
ucValues	Thew new values for the bits. The value for the first bit starting at usBitOffset is the LSB of the value ucValues

 ucBits[2] = {0, 0};

 // Set bit 4 to 1 (read: set 1 bit starting at bit offset 4 to value 1)
 xMBUtilSetBits( ucBits, 4, 1, 1 );

 // Set bit 7 to 1 and bit 8 to 0.
 xMBUtilSetBits( ucBits, 7, 2, 0x01 );

 // Set bits 8 - 11 to 0x05 and bits 12 - 15 to 0x0A;
 xMBUtilSetBits( ucBits, 8, 8, 0x5A);

Definition at line 47 of file mbutils.cpp.