Datasheet

© 2008 Microchip Technology Inc. DS39631E-page 255
PIC18F2420/2520/4420/4520
REGISTER 23-8: CONFIG6L: CONFIGURATION REGISTER 6 LOW (BYTE ADDRESS 30000Ah)
U-0 U-0 U-0 U-0 R/C-1 R/C-1 R/C-1 R/C-1
— — — —WRT3
(1)
WRT2
(1)
WRT1 WRT0
bit 7 bit 0
Legend:
R = Readable bit C = Clearable bit U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed u = Unchanged from programmed state
bit 7-4 Unimplemented: Read as ‘0’
bit 3 WRT3: Write Protection bit
(1)
1 = Block 3 (006000-007FFFh) not write-protected
0 = Block 3 (006000-007FFFh) write-protected
bit 2 WRT2: Write Protection bit
(1)
1 = Block 2 (004000-005FFFh) not write-protected
0 = Block 2 (004000-005FFFh) write-protected
bit 1 WRT1: Write Protection bit
1 = Block 1 (002000-003FFFh) not write-protected
0 = Block 1 (002000-003FFFh) write-protected
bit 0 WRT0: Write Protection bit
1 = Block 0 (000800-001FFFh) not write-protected
0 = Block 0 (000800-001FFFh) write-protected
Note 1: Unimplemented in PIC18F2420/4420 devices; maintain this bit set.
REGISTER 23-9: CONFIG6H: CONFIGURATION REGISTER 6 HIGH (BYTE ADDRESS 30000Bh)
R/C-1 R/C-1 R/C-1 U-0 U-0 U-0 U-0 U-0
WRTD WRTB WRTC
(1)
— — — — —
bit 7 bit 0
Legend:
R = Readable bit C = Clearable bit U = Unimplemented bit, read as ‘0’
-n = Value when device is unprogrammed u = Unchanged from programmed state
bit 7 WRTD: Data EEPROM Write Protection bit
1 = Data EEPROM not write-protected
0 = Data EEPROM write-protected
bit 6 WRTB: Boot Block Write Protection bit
1 = Boot block (000000-0007FFh) not write-protected
0 = Boot block (000000-0007FFh) write-protected
bit 5 WRTC: Configuration Register Write Protection bit
(1)
1 = Configuration registers (300000-3000FFh) not write-protected
0 = Configuration registers (300000-3000FFh) write-protected
bit 4-0 Unimplemented: Read as ‘0’
Note 1: This bit is read-only in normal execution mode; it can be written only in Program mode.