T89C5115_08 ATMEL [ATMEL Corporation], T89C5115_08 Datasheet - Page 25

• Manufacturer Part Number: T89C5115_08
• Description: Low Pin Count 8-bit Microcontroller with A/D Converter and 16 KBytes Flash Memory
• Manufacturer: ATMEL [ATMEL Corporation]

Upper 128 Bytes RAM
Expanded RAM
4128G–8051–02/08
Figure 10. Lower 128 Bytes Internal RAM Organization
The upper 128 Bytes of RAM are accessible from address 80h to FFh using only indirect
addressing mode.
The on-chip 256 Bytes of expanded RAM (XRAM) are accessible from address 0000h to
00FFh using indirect addressing mode through MOVX instructions. In this address
range.
Note:
Lower 128 Bytes RAM, Upper 128 Bytes RAM, and expanded RAM are made of volatile
memory cells. This means that the RAM content is indeterminate after power-up and
must then be initialized properly.
30h
20h
18h
10h
08h
00h
7Fh
2Fh
1Fh
17h
0Fh
07h
bit-Addressable Space
(bit Addresses 0-7Fh)
4 Banks of
8 Registers
R0-R7
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