PIC12F629/675
The EEPROM data memory allows byte read and write.
A byte write automatically erases the location and
writes the new data (erase before write). The EEPROM
data memory is rated for high erase/write cycles. The
write time is controlled by an on-chip timer. The write
time will vary with voltage and temperature as well as
from chip to chip. Please refer to AC Specifications for
exact limits.
8.0
DATA EEPROM MEMORY
The EEPROM data memory is readable and writable
during normal operation (full VDD range). This memory
is not directly mapped in the register file space.
Instead, it is indirectly addressed through the Special
Function Registers. There are four SFRs used to read
and write this memory:
• EECON±
When the data memory is code protected, the CPU
may continue to read and write the data EEPROM
memory. The device programmer can no longer access
this memory.
• EECON2 (not a physically implemented register)
• EEDATA
• EEADR
Additional information on the Data EEPROM is
available in the PICmicro™ Mid-Range Reference
Manual, (DS33023).
EEDATA holds the 8-bit data for read/write, and
EEADR holds the address of the EEPROM location
being accessed. PIC±2F629/675 devices have ±28
bytes of data EEPROM with an address range from 0h
to 7Fh.
REGISTER 8-1:
EEDAT — EEPROM DATA REGISTER (ADDRESS: 9Ah)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
EEDAT7 EEDAT6 EEDAT5 EEDAT4
bit 7
EEDAT3
EEDAT2 EEDAT± EEDAT0
bit 0
bit 7-0
EEDATn: Byte value to write to or read from Data EEPROM
Legend:
R = Readable bit
W = Writable bit
’±’ = Bit is set
U = Unimplemented bit, read as ‘0’
’0’ = Bit is cleared x = Bit is unknown
- n = Value at POR
REGISTER 8-2:
EEADR — EEPROM ADDRESS REGISTER (ADDRESS: 9Bh)
U-0
—
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
EADR0
bit 0
EADR6
EADR5
EADR4
EADR3
EADR2 EADR±
bit 7
bit 7
Unimplemented: Should be set to '0'
bit 6-0
EEADR: Specifies one of ±28 locations for EEPROM Read/Write Operation
Legend:
R = Readable bit
W = Writable bit
’±’ = Bit is set
U = Unimplemented bit, read as ‘0’
’0’ = Bit is cleared x = Bit is unknown
- n = Value at POR
2003 Microchip Technology Inc.
DS41190C-page 47
MICROCHIP [ MICROCHIP ]
