ABL electronic PIC12 Benutzerhandbuch

Referring to declarations from the previous example:

mu.d = 4.016;

Lcd_Out_Cp(FloatToStr(mu.d));

// OK: displays mu.d = 4.016

Lcd_Out_Cp(IntToStr(mu.i));

// peculiar result

pm->i = 3;

Lcd_Out_Cp(IntToStr(mu.i));

// OK: displays mu.i = 3

The second 

Lcd_Out_Cp

is legal, since 

mu.i

is an integral type. However, the bit

pattern in 

mu.i

corresponds to parts of the previously assigned 

double

. As such,

it probably does not provide a useful integer interpretation.

When properly converted, a pointer to a union points to each of its members, and
vice versa.

Bit fields are specified numbers of bits that may or may not have an associated
identifier. Bit fields offer a way of subdividing structures into named parts of user-
defined sizes.

mikroC implementation of bit fields requires you to set aside a structure for the
purpose, i.e. you cannot have a structure containing bit fields and other objects.
Bit fields structure can contain up to 8 bits.

You cannot take the address of a bit field.

Note: If you need to handle specific bits of 8-bit variables (char and unsigned
short) or registers, you don’t need to declare bit fields. Much more elegant solu-
tion is to use mikroC’s intrinsic ability for individual bit access — see Accessing
Individual Bits for more information.

Bit fields can be declared only in structures. Declare a structure normally, and
assign individual fields like this (fields need to be unsigned):

tag { unsigned bitfield-declarator-list; }

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