Mikroelektronika MIKROE-724 データシート

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mikoBasic PRO for dsPIC30/33 and PIC24
MikroElektronika
Logical Operations on Bit Level
and
0
1
0
0
0
1
0
1
or
0
1
0
0
1
1
1
1
xor
0
1
0
0
1
1
1
0
not
0
1
1
0
The bitwise operators 
and, or, 
and
 xor
 perform logical operations on the appropriate pairs of bits of their oper-
ands. The operator 
not
 complements each bit of its operand. For example:
$1234 and $5678        ‘ equals $1230 
‘ because ..
‘ $1234 : 0001 0010 0011 0100
‘ $5678 : 0101 0110 0111 1000
‘ ----------------------------
‘   and : 0001 0010 0011 0000
‘ .. that is, $1230
‘ Similarly:
$1234 or  $5678        ‘ equals $567C
$1234 xor $5678        ‘ equals $444C
not $1234              ‘ equals $EDCB
Unsigned and Conversions
If a number is converted from less complex to more complex data type, the upper bytes are filled with zeroes. If a 
number is converted from more complex to less complex data type, the data is simply truncated (the upper bytes are 
lost).
For example:
dim a as byte
dim b as word
‘ ...
  a = $AA
  b = $F0F0
  b = b and a
  ‘ a is extended with zeroes; b becomes $00A0