General puprose registers in 8051.

Well, in yesterday's podcast discussed on registers in 8051, two types of a register, general purpose registers are today's article all about.

The general purpose registers are called as RAM memory in 8051. It has 128 bytes of memory for this general purpose registers.

These general purpose registers are divided into 3 areas, those are 

Banks.

Bit addressable areas.

scratchpad areas.

                                   Image result for general purpose registers

Let we discuss clearly,

Banks

   In this bank, 4 types of banks are there like 

bank 0
bank 1
bank 2
bank 3

In each bank has 8 registers those are R0 to R7. All these general purpose registers are byte addressable registers. An image is shown in below for better understanding,

                                             General Purpose Registers



Data transferring from one general purpose register to another general purpose registers are impossible, so for this, we need PSW ( Program Status Word ) register.

What is Program Status Word:

    The PSW register is a bit and byte-addressable register. This register reflects the status of the operation that is carried out in the controller. The PSW register determines bank selection by an RS1 and RS0, as shown below. The physical address of the PSW starts from D0h and the individual bits are accessed with D0h to D7h.

                                             PSW Registers

   

Let's discuss very clearly on Program Status word in the next podcast. 

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