Mikroelektronika MIKROE-724 データシート

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mikoBasic PRO for dsPIC30/33 and PIC24

MikroElektronika

The mikroBasic PRO for dsPIC30/33 and PIC24 allows you to access individual bits of 16-bit variables. It also supports 

sbit and bit data types.

Lets use the Zero bit as an example. This bit is defined in the definition file of the particular MCU as: 

const Z = 1

dim   Z_bit as sbit at SR.B1

To access this bit in your code by its name, you can write something like this: 

SR.Z = 0

In this way, if Zero bit changes its position in the register, you are sure that the appropriate bit will be affected. 

But, if Zero bit is not located in the designated register, you may get errors.

Another way of accesing bits is by using the direct member selector (

.

) with a variable, followed by a primary expression. 

Primary expression can be variable, constant, function call or an expression enclosed by parentheses. For individual bit 

access there are predefined global constants 

B0, B1, … , B15

, or 

0, 1, … 15

, with 

15

 being the most significant bit:

SR.B0 = 0

SR.F5 = 1

i = 5

SR.(i+1) = 1

In this way, if the target bit changes its position in the register, you cannot be sure that you are invoking the appropriate bit.

This kind of selective access is an intrinsic feature of mikroBasic PRO for dsPIC30/33 and PIC24 and can be used 

anywhere in the code. Identifiers 

B0–B15

 are not case sensitive and have a specific namespace.

You may override them with your own members 

B0–B15

 within any given structure.

When using literal constants as bit designators instead of predefined ones, make sure not to exceed the appropriate type size.

Also, you can access the desired bit by using its alias name, in this case 

Z_bit

: 

Z_bit = 1

In this way, if the Zero bit changes its register or position in the register, you are sure that the appropriate bit will be affected.

See Predefined Globals and Constants for more information on register/bit names.