Predefined globals and constants, Accessing individual bits, Mikroc – ABL electronic PIC Microcontrollers PIC16 User Manual

Page 41

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Predefined Globals and Constants

To facilitate PIC programming, mikroC implements a number of predefined glob-
als and constants.

All PIC SFR registers are implicitly declared as global variables of

volatile

unsigned short

. These identifiers have external linkage, and are visible in the

entire project. When creating a project, mikroC will include an appropriate .def
file, containing declarations of available SFR and constants (such as

T0IE

,

INTF

,

etc). Identifiers are all in uppercase, identical to nomenclature in Microchip
datasheets. For the complete set of predefined globals and constants, look for
“Defs” in your mikroC installation folder, or probe the Code Assistant for specific
letters (Ctrl+Space in Editor).

Device Clock Constants

There are two built-in constants related to device clock:

___FOSC

and

___FCY

.

Constant

___FOSC

equals the frequency that is provided by an external oscillator,

while

___FCY

is the operating frequency of PIC. Both constants can be used any-

where in the code, and are automatically updated as you change target PIC in your
project. Source files that use these constants are recompiled any time the clock is
changed in IDE.

Accessing Individual Bits

mikroC allows you to access individual bits of 8-bit variables, types

char

and

unsigned short

. Simply use the direct member selector (

.

) with a variable,

followed by one of identifiers

F0

,

F1

, … ,

F7

. For example:

// If RB0 is set, set RC0:

if

(PORTB.F0) PORTC.F0 = 1;

There is no need for any special declarations; this kind of selective access is an
intrinsic feature of mikroC and can be used anywhere in the code. Identifiers

F0

F7

are not case sensitive and have a specific namespace.

Provided you are familiar with the particular chip, you can access bits by their
name:

INTCON.TMR0F = 0;

// Clear TMR0F

MikroElektronika: Development tools - Books - Compilers

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mikroC - C Compiler for Microchip PIC microcontrollers

mikroC

making it simple...

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