BRCLR - Branch if Bit n Clear ;flags(C)
BRCLR n,opr,rel ;PC <= PC + 3 + rel ;(DIR) 8 bit direct
;if Mn = 0 (n=0,1,..7)
Tests bit n (n=7,6,..0) in location M(opr) and branches if the bit is clear. M
can be any RAM or I/O register address in the $0000 to $00FF area of memory
(direct addressing).