Rev. 1.0
97
C8051F80x-83x
17. Special Function Registers
The direct-access data memory locations from 0x80 to 0xFF constitute the special function registers
(SFRs). The SFRs provide control and data exchange with the C8051F80x-83x's resources and peripher-
als. The CIP-51 controller core duplicates the SFRs found in a typical 8051 implementation as well as
implementing additional SFRs used to configure and access the sub-systems unique to the C8051F80x-
83x. This allows the addition of new functionality while retaining compatibility with the MCS-51 instruc-
tion set.
Table 17.1 lists the SFRs implemented in the C8051F80x-83x device family.
The SFR registers are accessed anytime the direct addressing mode is used to access memory locations
from 0x80 to 0xFF. SFRs with addresses ending in 0x0 or 0x8 (e.g., P0, TCON, SCON0, IE, etc.) are bit-
addressable as well as byte-addressable. All other SFRs are byte-addressable only. Unoccupied
addresses in the SFR space are reserved for future use. Accessing these areas will have an indeterminate
effect and should be avoided. Refer to the corresponding pages of the data sheet, as indicated in
Table 17.2, for a detailed description of each register.
Table 17.1. Special Function Register (SFR) Memory Map
F8
SPI0CN
PCA0L
PCA0H
PCA0CPL0 PCA0CPH0
P0MAT
P0MASK
VDM0CN
F0
B
P0MDIN
P1MDIN
EIP1
EIP2
PCA0PWM
E8 ADC0CN PCA0CPL1 PCA0CPH1 PCA0CPL2 PCA0CPH2
P1MAT
P1MASK
RSTSRC
E0
ACC
XBR0
XBR1
IT01CF
EIE1
EIE2
D8 PCA0CN
PCA0MD PCA0CPM0 PCA0CPM1 PCA0CPM2
CRC0IN
CRC0DATA
D0
PSW
REF0CN CRC0AUTO CRC0CNT
P0SKIP
P1SKIP
SMB0ADM
SMB0ADR
C8 TMR2CN
REG0CN
TMR2RLL
TMR2RLH
TMR2L
TMR2H
CRC0CN
CRC0FLIP
C0 SMB0CN
SMB0CF
SMB0DAT
ADC0GTL
ADC0GTH
ADC0LTL
ADC0LTH
B8
IP
CS0SS
CS0SE
ADC0MX
ADC0CF
ADC0L
ADC0H
B0
CS0CN
OSCXCN
OSCICN
OSCICL
HWID
REVID
FLKEY
A8
IE
CLKSEL
CS0DL
CS0DH
DERVID
A0
P2
SPI0CFG
SPI0CKR
SPI0DAT
P0MDOUT P1MDOUT
P2MDOUT
98
SCON0
SBUF0
CPT0CN
CS0MX
CPT0MD
CS0CF
CPT0MX
90
P1
CS0THL
CS0THH
88
TCON
TMOD
TL0
TL1
TH0
TH1
CKCON
PSCTL
80
P0
SP
DPL
DPH
PCON
0(8)
1(9)
2(A)
3(B)
4(C)
5(D)
6(E)
7(F)
Note:
SFR Addresses ending in 0x0 or 0x8 are bit-addressable locations, and can be used with bitwise instructions.