PIC18F2480 MICROCHIP [Microchip Technology], PIC18F2480 Datasheet - Page 360

• Manufacturer Part Number: PIC18F2480
• Description: 28/40/44-Pin Enhanced Flash Microcontrollers with ECAN Technology, 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2480/2580/4480/4580
TABLE 24-3:
24.5.1
The program memory may be read to or written from
any location using the table read and table write
instructions. The device ID may be read with table
reads. The configuration registers may be read and
written with the table read and table write instructions.
In normal execution mode, the CPn bits have no direct
effect. CPn bits inhibit external reads and writes. A
block of user memory may be protected from table
writes if the WRTn configuration bit is ‘0’. The EBTRn
bits control table reads. For a block of user memory
with the EBTRn bit set to ‘0’, a table read instruction
that executes from within that block is allowed to read.
FIGURE 24-6:
DS39637A-page 358
300008h
300009h
30000Ah
30000Bh
30000Ch
30000Dh
Legend: Shaded cells are unimplemented.
Results: All table writes disabled to Blockn whenever WRTn = 0.
TBLPTR = 0008FFh
Register Values
File Name
*
PC = 00BFFEh
PC = 003FFEh
Unimplemented in PIC18FX480 devices; maintain this bit set.
PROGRAM MEMORY
CODE PROTECTION
CONFIG5L
CONFIG5H
CONFIG6L
CONFIG6H
CONFIG7L
CONFIG7H
SUMMARY OF CODE PROTECTION REGISTERS
TABLE WRITE (WRTn) DISALLOWED
WRTD
Bit 7
CPD
—
—
—
—
EBTRB
WRTB
Bit 6
CPB
—
—
—
Program Memory
Preliminary
WRTC
Bit 5
TBLWT*
TBLWT*
—
—
—
—
—
A table read instruction that executes from a location
outside of that block is not allowed to read and will
result in reading ‘0’s. Figures 24-6 through 24-8
illustrate table write and table read protection.
Bit 4
—
—
—
—
—
—
Note:
000000h
0007FFh
000800h
003FFFh
004000h
007FFFh
008000h
00BFFFh
00C000h
00FFFFh
EBTR3*
WRT3*
CP3*
Code protection bits may only be written to
a ‘0’ from a ‘1’ state. It is not possible to
write a ‘1’ to a bit in the ‘0’ state. Code
protection bits are only set to ‘1’ by a full
chip erase or block erase function. The full
chip erase and block erase functions can
only be initiated via ICSP or an external
programmer.
Bit 3
—
—
—
Configuration Bit Settings
EBTR2
WRT2
Bit 2
CP2
WRTB, EBTRB = 11
 2004 Microchip Technology Inc.
WRT0, EBTR0 = 01
WRT1, EBTR1 = 11
WRT2, EBTR2 = 11
WRT3, EBTR3 = 11
—
—
—
EBTR1
WRT1
Bit 1
CP1
—
—
—
EBTR0
WRT0
Bit 0
CP0
—
—
—