PIC18F4620-E/P Microchip Technology Inc., PIC18F4620-E/P Datasheet - Page 266

• Manufacturer Part Number: PIC18F4620-E/P
• Description: 40 Pin, 64 KB Flash, 3968 RAM, 36 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F4620-E/P

• A/d Inputs: 13-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 10 MIPS
• Eeprom Memory: 1024 Bytes
• Input Output: 36
• Interface: SPI/I2C/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 40-pin PDIP
• Programmable Memory: 64K Bytes
• Ram Size: 4K Bytes
• Speed: 40 MHz
• Timers: 1-8 bit, 3-16 bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PIC18F2525/2620/4525/4620
23.5.1
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 23-6:
DS39626B-page 264
TBLPTR = 0008FFh
Results: All table writes disabled to Blockn whenever WRTn = 0.
Register Values
PROGRAM MEMORY
CODE PROTECTION
PC = 00BFFEh
PC = 003FFEh
TABLE WRITE (WRTn) DISALLOWED
Program Memory
Preliminary
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 23-6 through 23-8 illustrate table
write and table read protection.
Note:
000000h
0007FFh
000800h
003FFFh
004000h
007FFFh
008000h
00BFFFh
00C000h
00FFFFh
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 operation or an
external programmer.
Configuration Bit Settings
WRTB, EBTRB = 11
WRT0, EBTR0 = 01
WRT1, EBTR1 = 11
WRT2, EBTR2 = 11
WRT3, EBTR3 = 11
 2004 Microchip Technology Inc.