2024年9月12日 · The Flag register is a 8-bit register in the 8085 microprocessor that contains information about the status of the arithmetic and logic operations performed by the processor. The bits in the Flag register are used to indicate whether the result of an operation is zero, positive, negative, or if there was a carry or borrow during the operation.

The lower 8 bits of the FLAGS register is also open to direct load/store manipulation by SAHF and LAHF (load/store AH into flags). The ability to push and pop FLAGS registers lets a program manipulate information in the FLAGS in ways for which …

2023年5月13日 · Bitwise flag manipulation is a powerful technique that allows you to use each bit in an 8-bit variable as an individual flag. This approach allows you to store 8 boolean values in a single byte, making it both memory-efficient and fast. In this tutorial, we will dive into bitwise flag manipulation, exploring how to set, read, and clear flags.

For example, consider the 8-bit representations of the mask for food and the mask for water. Suppose you want to create a composite mask to determine if the player has both food and water. If you create the mask using the bitwise & operator, you get the following:

2020年7月19日 · In this post, I will talk about the ALU and the flags register of my 8-bit computer. The arithmetical logical unit (ALU) is where all the computation happens in a computer. The ALU of this computer is very simple and only has the option to add or subtract numbers. So something like multiplication would have to be implemented in software.

Carry Flag is a flag set when: a) two unsigned numbers were added and the result is larger than "capacity" of register where it is saved. Ex: we wanna add two 8 bit numbers and save result in 8 bit register. In your example: 255 + 9 = 264 which is more that 8 bit register can store.

2023年9月10日 · In 8085 microprocessor, the flags register can have a total of eight flags. Thus a flag can be represented by 1 bit of information. But only five flags are implemented in 8085. And they are: Zero flag (Z). The respective position of these …

This flag is set whenever there has been a carry out of, or a borrow into, the higher order bit of the result. The flag is used by the instructions that add amd subtract multibyte numbers. 1-carry out from MSB bit on addition or borrow into MSB bit on subtraction

8051 Flag Bits and PSW Register. The program status word (PSW) register is an 8-bit register, also known as flag register. It is of 8-bit wide but only 6-bit of it is used. The two unused bits are user-defined flags. Four of the flags are called conditional flags, which means that they indicate a condition which results after an instruction is ...

2019年7月11日 · FlagNr contains the zero based bit index so a value of 0 is the first bit in the first array element. static uint8_t masks[] = {0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01}; size_t index = FlagNr % 8; size_t xndex = FlagNr / 8; thing->Flags[xndex] |= masks[index]; I think the OP wants the bit indexing to be reversed.