Does your count go past 30?
If you just need to detect when the count is 30, then it is better to
XOR your counter with 30 and check if the result is zero:

(assuming you are using a regular PIC device)
    movlw    30
    xorwf      counter,w
    btfsc        STATUS,Z
    goto        do_something

The test you suggested will do the something for counter values of 30
and 31 (0x1e and 0x1f), because you are ignoring bit zero.
If your counter goes past 30, your test will succeed again for values of
62 and 63 (0x3e and 0x3f), and also for 0x5e, 0x5f, 0x7e, 0x7f, 0x9e,
0x9f, 0xbe, 0xbf, 0xde, 0xdf, 0xfe, 0xff.


Isaac


Em 10/02/2013 17:34, mircea2012 escreveu:
> Hy.=20
> For example if I have a variable count =3D 30.=20
> In binary sistem 30 =3D 11110.=20
> I must do something like that :=20
> if bit 4 is logic one=20
>    AND=20
> bit 3 is logic one=20
>    AND=20
> bit 2 is logic one=20
>    AND=20
> bit 1 is logic one=20
> DO SOMETHING.=20
> Thank you.
>
>
>
> --
> View this message in context: http://microcontrollers.2385.n7.nabble.com/=
PIC-How-to-ANDed-bitwise-in-assembler-tp180767.html
> Sent from the MicroControllers - PIC mailing list archive at Nabble.com.

--=20
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