W79E825A Datasheet, PDF (14/127 Pages) Winbond – 8-BIT MICROCONTROLLER

W79E825A/824A/823B/822B Data Sheet
FFH
80H
7FH
00H
Indirect
RAM
Addressing
SFR
Direct
Addressing
Only
Direct
&
Indirect
RAM
Addressing
RAM and SFR Data Memory Space
Figure 7-3: W79E825 and W79E824 RAM and SFR memory map
FFH
Unused
Indirect
RAM
80H
7FH
Direct & Indirect
RAM
Addressing
00H
SFR
Direct
Addressing
Only
RAM and SFR Data Memory Space
Figure 7-4: W79E823 and W79E822 RAM and SFR memory map
Since the scratch-pad RAM is only 256/128 bytes it can be used only when data contents are small.
There are several other special purpose areas within the scratch-pad RAM. These are described as
follows.
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