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CHAPTER 3 REGISTERS
3.7Direct Banks
The direct bank is in 0080H to 047FH of direct area, and composed of 128 bytes ⋅ 8 banks. The access that uses direct addressing and bit direct addressing in operand address 80H to FFH can be extended to 8 direct banks according to the value of the direct bank pointer (DP). The current bank is indicated by the direct bank pointer (DP).
■Direct Bank
Figure 3.7-1 shows the configuration of a direct bank.
The access that uses direct addressing and bit direct addressing in operand address 80H to FFH can be extended to 8 direct banks according to the value of the direct bank pointer (DP). The access that uses direct addressing and bit direct addressing in operand address 00H to 7FH is not affected by the value of the direct bank pointer (DP). This access is directed to fixed direct area 0000H to 007FH.
Figure 3.7-1 Configuration of Direct Bank
Memory
Direct addressing
and
Operand address in bit direct addressing
Direct bank 7
(DP=111)
Direct bank 1
(DP=001)
047FH
0400H
017FH
0100H
Direct area
FFH 80H
7FH
00H
Direct bank 0
(DP=000)
Fixed direct area
00FFH 0080H
007FH
0000H
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