Opcode 0xed in binary code#

This can be thought of as 'Accumulator Logical Exclusive OR 255' or as '255-Accumulator.' If the operandВ refers to a bit of an output Port, the value that will be complemented is based on the last value written to that bit, not the last value read from it.Дescription:В DA adjusts the contents of the Accumulator to correspond to a BCD (Binary Coded Decimal) number after two BCD numbers have been added by the ADD or ADDC instruction. If operandВ is the Accumulator then all the bits in the Accumulator will be reversed. If operandВ is a single bit then the state of the bit will be reversed. Clearing the Accumulator sets the Accumulator's value to 0.Дescription:В CPL complements operand, leaving the result in operand. If the register is a bit (including the carry bit), only the specified bit is affected. The Carry bit (C)В is set if operand1В is less than operand2, otherwise it is cleared.Дescription:В CLR clears (sets to 0) all the bit(s) of the indicated register. If the two operands are equal program flow continues with the instruction following the CJNE instruction. A logical 'AND' compares the bits of each operand and sets the corresponding bit in the resulting byte only if the bit was set in both of the original operands, otherwise the resulting bit is cleared.Дescription:В CJNE compares the value of operand1В and operand2В and branches to the indicated relative address if operand1В and operand2В are not equal.

Opcode 0xed in binary code#

Since only 11 bits of the Program Counter are affected by AJMP, jumps may only be made to code located within the same 2k block as the first byte that follows AJMP.Дescription:В ANL does a bitwise 'AND' operation between operand1В and operand2, leaving the resulting value in operand1. Bits 3-7 of the most-significant-byte of the Program Counter remain unchaged. The new value for the Program Counter is calculated by replacing the least-significant-byte of the Program Counter with the second byte of the AJMP instruction, and replacing bits 0-2 of the most-significant-byte of the Program Counter with 3 bits that indicate the page of the byte following the AJMP instruction. Otherwise, the Overflow flag is cleared.Дescription:В AJMP unconditionally jumps to the indicated code address. In other words, if the addition of the Accumulator, operandВ and (in the case of ADDC) the Carry flag treated as signed values results in a value that is out of the range of a signed byte (-128 through +127) the Overflow flag is set. The Overflow (OV)В bit is set if there is a carry-out of bit 6 or out of bit 7, but not both. Otherwise, the Auxillary Carry flag is cleared. In other words, if the unsigned summed value of the low nibble of the Accumulator, operandВ and (in the case of ADDC) the Carry flag exceeds 15 the Auxillary Carry flag is set.

The Auxillary Carry (AC)В bit is set if there is a carry-out of bit 3. In other words, if the unsigned summed value of the Accumulator, operandВ and (in the case of ADDC) the Carry flag exceeds 255 Carry is set. The Carry bit (C)В is set if there is a carry-out of bit 7. ADD and ADDC function identically except that ADDC adds the value of operand as well as the value of the Carry flag whereas ADD does not add the Carry flag to the result. Since only 11 bits of the Program Counter are affected by ACALL, calls may only be made to routines located within the same 2k block as the first byte that follows ACALL.ДЄdd Accumulator, Add Accumulator With CarryДescription:В Description: ADD and ADDC both add the value operandВ to the value of the Accumulator, leaving the resulting value in the Accumulator.

The new value for the Program Counter is calculated by replacing the least-significant-byte of the Program Counter with the second byte of the ACALL instruction, and replacing bits 0-2 of the most-significant-byte of the Program Counter with 3 bits that indicate the page. The Program Counter is then updated so that program execution continues at the indicated address. ACALL pushes the address of the instruction that follows ACALL onto the stack, least-significant-byte first, most-significant-byte second. Description:В ACALL unconditionally calls a subroutine at the indicated code address.