NOT making sense

[Jeff-20]

I feel like it has been discussed here, or I read about it in a book somewhere... But can anyone explain how the boolean operator NOT works on the VIC?

My mind tells me:
NOT 0 = 1
NOT 1 = 0

But my VIC tells me:
NOT 0 = -1
NOT 1 = -2

I know CBM BASIC returns -1 as TRUE and 0 as FALSE, but it doesn't make clear to me why -2 is here... like on a BIT level.

[Mike]

NOT 1 = NOT(%0000 0000 0000 0001) = %1111 1111 1111 1110 = -2 in two's-complement with 16-bit integers.

[Jeff-20]

NOT 1 = NOT(%0000 0000 0000 0001) = %1111 1111 1111 1110 = -2 in two's-complement with 16-bit integers.

Thanks, Mike! I finally get it now.