Direct Bank Pointer (Dp) - Fujitsu 8FX Hardware Manual

MB95630H Series
2.1.2

Direct Bank Pointer (DP)

The direct bank pointer (DP) in bit10 to bit8 of the program status (PS) register
specifies the area to be accessed by direct addressing.
■ Configuration of Direct Bank Pointer (DP)
Figure 2.1-4 shows the configuration of the direct bank pointer.
RP
bit15 bit14 bit13 bit12 bit11 bit10 bit9
PS
R4 R3 R2
The area of "0x0000 to 0x007F" and that of "0x0090 to 0x047F" can be accessed by direct
addressing. Access to 0x0000 to 0x007F is specified by an operand regardless of the value in
the direct bank pointer. Access to 0x0090 to 0x047F is specified by the value of the direct bank
pointer and the operand.
Table 2.1-1 shows the relationship between the direct bank pointer (DP) and the access area;
Table 2.1-2 lists the direct addressing instructions.
Table 2.1-1 Direct Bank Pointer and Access Area
Direct bank pointer (DP[2:0])
0bXXX (It does not affect mapping.)
0b000 (Initial value)
0b001
0b010
0b011
0b100
0b101
0b110
0b111
*: The available access area varies among products. For details, refer to the device data sheet.
MN702-00009-2v0-E
Figure 2.1-4 Configuration of Direct Bank Pointer
DP
bit8
R1 R0 DP2 DP1 DP0
Operand-specified dir
0x0000 to 0x007F
0x0090 to 0x00FF
0x0080 to 0x00FF
FUJITSU SEMICONDUCTOR LIMITED
CCR
bit7 bit6 bit5 bit4 bit3
H I IL1 IL0 N
0x0000 to 0x007F
0x0090 to 0x00FF
0x0100 to 0x017F
0x0180 to 0x01FF
0x0200 to 0x027F
0x0280 to 0x02FF
0x0300 to 0x037F
0x0380 to 0x03FF
0x0400 to 0x047F
CHAPTER 2 CPU
2.1 Dedicated Registers
DP
bit2 bit1 bit0 initial value
0b000
Z V C
Access area*
7