How do I check (or set) a group of consecutive bits within a byte?

[Ioannis]

Bitwise and Logical are two different things. All versions do support them.

You will use Logical AND or &&, OR or ||, XOR or ^^, ANDNOT, ORNOT, XORNOT in TRUE/FALSE case. If value is 0 then it is treated as FALSE. Any other value is treated as TRU. So, in IF-THEN statement you can check if the values are or are not zero.

Example:

A=2:B=0

IF A AND B THEN C=1

C will be set to 1 if both A and B variables are not zero.

But Bitwise Operators act on each and every bit of the variable using boolean maths.

If you want to isolate bits a variables you want to use the & operand.

If you want to set a bit then | is your operand to use.

Example (from the Book):

B0=B0 & %00000001 'Isolate bit 0 of B0

B0=B0 | %00000001 'Set bit 0 of B0

B0=B0 ^ %00000001 'Reverse state of bit 0 of B0

So Hank, you want to use & in your case.

ADCON0 = ADCON & %00011101

Ioannis

[Charlie]

Can you tell me which "Book" this example is from? I'm happy to be corrected - this is exactly what I was looking for - but It's certainly not in my 2.6 Manual.

[Ioannis]

From 2.4 page 36
From 2.6 page 42

or

From 3.0 pages 70 an 78

Ioannis

[Charlie]

You're absolutely right!

If it's any help to anyone else, when I searched for logical AND, the first instance that came up is on page 43. The proper names for the boolean operations (AND, OR, XOR) are not used on P42.

[HankMcSpank]

Well, hopefully some good has come from my initial problem (which I've now sorted/worked around by other means)...thanks for your input everyone!

[Mike, K8LH]

Hank, does PBP allow you to XOR a bit?

adcon0.2 = adcon0.2 XOR 1

That's pretty much how I would do it BoostC ( adcon0.2 ^= 1 ).

Cheerful regards, Mike

[Ioannis]

This adcon0.2 = adcon0.2 XOR 1 does a logical XOR.

You need bitwise XOR:

adcon0.2 = adcon0.2 ^ 1

Ioannis