71M6531F-IM/F Maxim Integrated Products, 71M6531F-IM/F Datasheet - Page 21

• Manufacturer Part Number: 71M6531F-IM/F
• Description: IC ENERGY METER 256KB 68-QFN
• Manufacturer: Maxim Integrated Products

Specifications of 71M6531F-IM/F

• Mounting Style: SMD/SMT
• Package / Case: QFN-68
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

to as USR2). It defines the high byte of a 16-bit address when reading or writing XDATA with the instruction
MOVX A,@Ri or MOVX @Ri,A.
Internal Data Memory Map and Access
The Internal data memory provides 256 bytes (0x00 to 0xFF) of data memory. The internal data memory
address is always 1 byte wide.
The Special Function Registers (SFR) occupy the upper 128 bytes. The SFR area of internal data memory
is available only by direct addressing
bytes form four banks of eight registers (R0-R7). Two bits on the program memory status word (PSW) select
which bank is in use. The next 16 bytes form a block of bit addressable memory space at bit addresses
0x00-0x7F. All of the bytes in the lower 128 bytes are accessible through direct or indirect addressing.
Only a few addresses in the SFR memory space are occupied, the others are not implemented. A read
access to unimplemented addresses will return undefined data, while a write access will have no effect.
SFRs specific to the 71M6531D/F and 71M6532D/F are shown in bold print on a gray field. The registers
at 0x80, 0x88, 0x90, etc., are bit addressable, all others are byte addressable. See the restrictions for the
INTBITS register in
FDS 6531/6532 005
An alternative data pointer is available in the form of the PDATA register (SFR 0xBF), sometimes referred
Internal RAM. The lower 128 bytes contain working registers and bit addressable memory. The lower 32
1.4.2
A map of the Special Function Registers is shown in Table 9.
v1.3
Hex/
Bin
E8
E0
D8
D0
C8
C0
B8
B0
A8
A0
F8
F0
98
90
88
80
Special Function Registers (SFRs)
Addressable
INTBITS
IFLAGS
WDCON
T2CON
S0CON
IRCON
TCON
Address Range
X000
0x80
0x30
0x20
0x00
IEN1
IEN0
PSW
Bit
P3
P2
P1
P0
B
A
Table
S0BUF
TMOD
0xFF
0x7F
0x2F
0x1F
X001
DIR2
DIR1
IP1
IP0
© 2005-2010 TERIDIAN Semiconductor Corporation
14.
SP
Table 8
Table 9: Special Function Register Map
FLSHCTL
Special Function Registers (SFRs)
S0RELH
Table 8: Internal Data Memory Map
S0RELL
X010
DIR0
IEN2
DPS
DPL
TL0
. Indirect addressing of this area accesses the upper 128 bytes of
shows the internal data memory map.
Direct addressing
S1RELH
S1CON
X011
DPH
TL1
Byte Addressable
Register banks R0…R7
Byte addressable area
Bit addressable area
ERASE
S1BUF
DPL1
X100
TH0
S1RELL
Data Sheet 71M6531D/F-71M6532D/F
DPH1
X101
TH1
Indirect addressing
FL_BANK
EEDATA
CKCON
X110
RAM
EECTRL
PGADR
PDATA
PCON
X111
Bin/
Hex
EF
DF
D7
CF
C7
BF
B7
AF
A7
FF
F7
E7
9F
8F
97
87
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