Mikroelektronika MIKROE-742 데이터 시트

Binary operators 

shl

and 

shr

move the bits of the left operand by a number of posi-

tions specified by the right operand, to the left or right, respectively. Right operand
has to be positive and less than 255.

With shift left (

shl

), left most bits are discarded, and “new” bits on the right are

assigned zeroes. Thus, shifting unsigned operand to the left by 

n

positions is equiv-

alent to multiplying it by 2n if all discarded bits are zero. This is also true for signed
operands if all discarded bits are equal to the sign bit.

With shift right (

shr

), right most bits are discarded, and the “freed” bits on the left

are assigned zeroes (in case of unsigned operand) or the value of the sign bit (in
case of signed operand). Shifting operand to the right by n positions is equivalent to

dividing it by 2n.

Although mikroPascal PRO for AVR does not support 

boolean

type, you have

Boolean operators at your disposal for building complex conditional expressions.
These operators conform to standard Boolean logic and return either 

TRUE

(all ones)

or

FALSE 

(zero):

Boolean operators associate from left to right. Negation operator not associates
from right to left.

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- SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD

CHAPTER 5

and

logical AND

or

logical OR

xor

logical exclusive OR (XOR)

not

logical negation