Question
Download Solution PDFCarry flag is not affected after the execution of
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFADD: Add Register to Accumulator
Description: The content of the operand (register or memory) are added to the contents of the accumulator and the result is stored in the accumulator. If the operand is a memory location, that is indicated by the 16-bit address in the HL register.
Flags: All flags are modified to reflect the result of the addition.
INR: Increment Register Pair by 1
Description: The contents of the designated register/memory are incremented by 1 and the results are stored in the same place. If the operand is a memory location, it is specified by the contents of HL register pair.
Flags: S, Z, P, AC are modified to reflect the result of the operation. CY is not modified.
SBB: Subtract Source and Borrow from Accumulator
Description: The contents of the operand (register or memory) and the Borrow flag are subtracted from the contents of the accumulator and the results are placed in the accumulator. The contents of the operand are not altered; however, the previous Borrow flag is reset.
Flag: All flags are altered to reflect the result of the subtraction.
Important:
Different arithmetic instructions and the flags affected are mentioned below:
|
Instruction |
S |
Z |
AC |
P |
Cy |
|
INR, DCR |
Yes |
Yes |
Yes |
Yes |
No |
|
DAD |
No |
No |
No |
No |
Yes |
|
ADD, ADC, SUB, SBB, DAA |
Yes |
Yes |
Yes |
Yes |
Yes |
|
RAL, RLC, RAR, RRC |
No |
No |
No |
No |
Yes |