Subb instruction in 8051

8051 instruction set
subb a,r2
xrl in 8051
clr c instruction in 8051
cjne in 8051movx instruction in 8051
mul instruction in 8051
jnc instruction in 8051

Instruction. Flag. Instruction. Flag. C. OV. AC. C. OV. AC. ADD. X. X. X. CLR C. O. ADDC. X. X. X. CPL C. X. SUBB. X. X. X. ANL C,bit. X. MUL. O. X.THE STANDARD 8051/52 CPU REGISTERS. before executing a SUBB instruction, this indicates that a borrow was needed for the previous step in a. Description: SUBB subtract the value of operand and the Carry Flag from the value of the Accumulator, leaving the resulting value in the Accumulator. The value 8051 / 8052 Microcontroller Instruction Set SUBB - Subtract from Accumulator with Borrow Description: SUBB subtract the value of operand from the value of the In many microprocessors there a^e two different instructions for subtraction: SUB and SUBB (subtract with borrow). In the 8051 we have only SUBB.