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Internal Data Memory (256 Byte) and SFR

The Figure below shows the Internal Memory and Special Function Registers (SFR) map.

0xFF .. 0x80Upper Internal RAM shared with Stack space (indirect addressing)SFR Special Function Registers (direct addressing)
0x7F .. 0x30Lower Internal RAM shared with Stack space (direct & indirect addressing)
0x2F .. 0x20bit addressable area
0x1F .. 0x004 banks, R0-R7 each

The lower internal RAM consists of four register banks with eight registers each, a bit- addressable segment with 128 bits (16 bytes) that begins at 0x20, and a scratchpad area with 208 bytes is embedded. With indirect addressing mode ranging from 0x80 to 0xFF, the highest 128 bytes is accessed as an internal memory.
But with direct addressing mode ranging from 0x80 to 0xFF, this area is accessed as a SFR memory: