C8051F360/1/2/3/4/5/6/7/8/9
9.4.7. Register Descriptions
Following are descriptions of SFRs related to the operation of the CIP-51 System Controller. Reserved bits
should not be set to logic ‘1’. Future product versions may use these bits to implement new features in
which case the reset value of the bit will be logic ‘0’, selecting the feature's default state. Detailed descrip-
tions of the remaining SFRs are included in the sections of the data sheet associated with their corre-
sponding system function.
SFR Definition 9.5. SP: Stack Pointer
SFR Page:
all pages
SFR Address: 0x81
R/W
Bit7
R/W
Bit6
R/W
Bit5
R/W
Bit4
R/W
Bit3
R/W
Bit2
R/W
Bit1
R/W
Bit0
Reset Value
00000111
Bits 7–0: SP: Stack Pointer.
The Stack Pointer holds the location of the top of the stack. The stack pointer is incremented
before every PUSH operation. The SP register defaults to 0x07 after reset.
SFR Definition 9.6. DPL: Data Pointer Low Byte
SFR Page
all pages
SFR Address: 0x82
R/W
Bit7
R/W
Bit6
R/W
Bit5
R/W
Bit4
R/W
Bit3
R/W
Bit2
R/W
Bit1
R/W
Bit0
Reset Value
00000000
Bits 7–0: DPL: Data Pointer Low.
The DPL register is the low byte of the 16-bit DPTR. DPTR is used to access indirectly
addressed XRAM and Flash memory.
SFR Definition 9.7. DPH: Data Pointer High Byte
SFR Page:
all pages
SFR Address: 0x83
R/W
Bit7
R/W
Bit6
R/W
Bit5
R/W
Bit4
R/W
Bit3
R/W
Bit2
R/W
Bit1
R/W
Bit0
Reset Value
00000000
Bits 7–0: DPH: Data Pointer High.
The DPH register is the high byte of the 16-bit DPTR. DPTR is used to access indirectly
addressed XRAM and Flash memory.
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Rev. 1.0