The page in the manual says

Function: Compare and Jump if Not Equal
Description: CJNE compares the magnitudes of the first two operands, and branches if their values are not equal. The
branch destination is computed by adding the signed relative-displacement in the last instruction byte to
the PC, after incrementing the PC to the start of the next instruction. The carry flag is set if the unsigned
integer value of <dest-byte> is less than the unsigned integer value of <src-byte>; otherwise, the carry is
cleared. Neither operand is affected.