71M6521DE TERIDIAN [Teridian Semiconductor Corporation], 71M6521DE Datasheet - Page 18

• Manufacturer Part Number: 71M6521DE
• Description: Energy Meter IC
• Manufacturer: TERIDIAN [Teridian Semiconductor Corporation]

Internal Data Memory: The lower 128 bytes contain working registers and bit-addressable memory. The lower 32 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 addressees 0x00-0x7F. All of the bytes in the lower 128
bytes are accessible through direct or indirect addressing. Table 6 shows the internal data memory map.
Special Function Registers (SFRs)
A map of the Special Function Registers is shown in Table 7.
Only a few addresses are occupied, the others are not implemented. SFRs specific to the 652X are shown in bold print. Any
read access to unimplemented addresses will return undefined data, while any write access will have no effect. The registers at
0x80, 0x88, 0x90, etc., are bit-addressable, all others are byte-addressable.
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Hex\Bin
E8
E0
D8
D0
C8
C0
B8
B0
A8
A0
F8
F0
98
90
88
80
Bit-address-
INTBITS
WDCON
T2CON
IRCON
S0CON
TCON
X000
IEN1
IEN0
able
WDI
PSW
P2
P1
P0
B
A
Address
0xFF
0x80
0x7F
0x30
0x2F
0x20
0x1F
0x00
S0BUF
TMOD
X001
DIR2
DIR1
IP1
IP0
SP
Special Function Registers
(SFRs)
IEN2
Table 7: Special Function Registers Locations
FLSHCTL
© 2005-2008 TERIDIAN Semiconductor Corporation
S0RELH
S0RELL
Direct addressing
X010
DIR0
DPL
DPS
TL0
Table 6: Internal Data Memory Map
S1RELH
S1CON
X011
DPH
TL1
Register banks R0…R7
Byte-addressable area
Byte-addressable
Bit-addressable area
ERASE
S1BUF
X100
DPL1
TH0
71M6521DE/71M6521FE
Indirect addressing
S1RELL
DPH1
X101
TH1
RAM
EEDATA
WDTREL
CKCON
Energy Meter IC
X110
EECTRL
PGADR
PCON
X111
USR2
DATASHEET
Bin/Hex
JANUARY 2008
DF
CF
BF
AF
FF
F7
EF
E7
D7
C7
B7
A7
9F
8F
97
87
v1.0