Introduction to Registers

Accumulator Register (AC)

An accumulator register is a CPU register that holds the result of an operation. It can be used as a temporary storage place for intermediate results and is usually located in each CPU core. The accumulator registers are called A0, A1, and so on.
Accumulators typically hold integer numbers or floating-point values. They may also store data such as the status flags which show whether eax contains zero or not.
Accumulator registers are very fast and efficient to use because they can be read from and written to without having to save them first in memory as general-purpose registers do. We also call these registers “accs” or “A’s”.

Condition code register (CCR)

Condition code register is a memory address where the result of comparison between two operands is stored. The bits in this location tell the computer what to do next with these two values, whether to compare them again or store them as an answer.
The condition code register is commonly abbreviated as CCR and it’s usually located at address 0x4C, but can vary according to different architectures. To know more about condition codes and how they work, keep reading!

Data Register (DR)

Data Register is a part of the CPU where data is stored. It’s one of the primary computing units, and it stores information in binary form. Data Register can store numbers, letters, or symbols- including punctuation marks like commas. The computer has multiple registers to work with at once; they’re just about as important as the processing unit itself!

Instruction Register (IR)

The instruction register is a part of the CPU that holds an instruction before it’s executed. The purpose of this is to keep track of what instructions are coming in, and then execute them one at a time. This prevents any information from being lost or misinterpreted during transmission between the processor and memory. It also keeps the data flow continuously so that all instructions are executed quickly without interruption.