Where are the working registers R0~R7 of the 51 MCU located in the internal RAM?-EEWORLD

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There are 32 working registers in 51 MCU, which are 00H--1FH units in RAM and divided into 4 groups, namely

Group 0: 00H--07H units,

1 group: 08H--0FH unit,

2 groups: 10H--17H units,

3 groups: 18H--1FH units,

The 8 units in each group correspond to R0--R7. Only one of the four groups is the current working register, and the 8 units in the current working register are used in the program. The current working register is determined by the third and fourth bits in the program status word PSW. In PSW, the four states of 00, 01, 10, and 11 of the two-bit combination of PSW4 and PSW3 specify the 0th, 1st, 2nd, and 3rd groups of the working registers, respectively. You only need to use instructions to change the two-bit state of PSW to change the current working register group. In this way, there are actually 32 working registers to choose from.

Reference address：Where are the working registers R0~R7 of the 51 MCU located in the internal RAM?

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