Microchip Technology ARD00385 Datenbogen

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PIC18F87K90 FAMILY
DS39957D-page 122
 2009-2011 Microchip Technology Inc.
REGISTER 8-1:
EECON1: DATA EEPROM CONTROL REGISTER 1
R/W-x
R/W-x
U-0
R/W-0
R/W-x
R/W-0
R/S-0
R/S-0
EEPGD
CFGS
FREE
WRERR
(
WREN
WR
RD
bit 7
bit 0
Legend:
S = Settable bit
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
EEPGD:
 Flash Program or Data EEPROM Memory Select bit
1
 = Access Flash program memory
0
 = Access data EEPROM memory
bit 6
CFGS:
 Flash Program/Data EEPROM or Configuration Select bit
1
 = Access Configuration registers
0
 = Access Flash program or data EEPROM memory
bit 5
Unimplemented: 
Read as ‘0’
bit 4
FREE: 
Flash Row Erase Enable bit
1
 = Erase the program memory row addressed by the TBLPTR on the next WR command 
(cleared by completion of an erase operation)
0
 = Perform write-only
bit 3
WRERR:
 Flash Program/Data EEPROM Error Flag bit
1
 = A write operation is prematurely terminated (any Reset during self-timed programming in normal
operation or an improper write attempt)
0
 = The write operation completed
bit 2
WREN:
 Flash Program/Data EEPROM Write Enable bit
1
 = Allows write cycles to Flash program/data EEPROM
0
 = Inhibits write cycles to Flash program/data EEPROM
bit 1
WR:
 Write-Control bit
1
 = Initiates a data EEPROM erase/write cycle, or a program memory erase cycle or write cycle 
(The operation is self-timed and the bit is cleared by hardware once the write is complete. The
WR bit can only be set (not cleared) in software.)
0
 = Write cycle to the EEPROM is complete
bit 0
RD:
 Read Control bit
1
 = Initiates an EEPROM read (Read takes one cycle. RD is cleared in hardware. The RD bit can only
be set (not cleared) in software. The RD bit cannot be set when EEPGD = 1 or CFGS = 1.)
0
 = Does not initiate an EEPROM read
Note 1:
When a WRERR occurs, the EEPGD and CFGS bits are not cleared. This allows tracing of the error 
condition.