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 3.7-1shows 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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Fujitsu F2MC-8FX manual Direct Banks, Configuration of Direct Bank