PIC18F45K80-I Datasheet, PDF (482/622 Pages) Microchip Technology – 28/40/44/64-Pin, Enhanced Flash Microcontrollers with ECAN and nanoWatt XLP Technology

PIC18F66K80 FAMILY
28.6.2
DATA EEPROM
CODE PROTECTION
The entire data EEPROM is protected from external
reads and writes by two bits: CPD and WRTD. CPD
inhibits external reads and writes of data EEPROM.
WRTD inhibits internal and external writes to data
EEPROM. The CPU can always read data EEPROM
under normal operation, regardless of the protection bit
settings.
28.6.3
CONFIGURATION REGISTER
PROTECTION
The Configuration registers can be write-protected.
The WRTC bit controls protection of the Configuration
registers. In normal execution mode, the WRTC bit is
readable only. WRTC can only be written via ICSP or
an external programmer.
28.7 ID Locations
Eight memory locations (200000h-200007h) are
designated as ID locations, where the user can store
checksum or other code identification numbers. These
locations are both readable and writable during normal
execution through the TBLRD and TBLWT instructions
or during program/verify. The ID locations can be read
when the device is code-protected.
28.8 In-Circuit Serial Programming
The PIC18F66K80 family of devices can be serially
programmed while in the end application circuit. This is
simply done with two lines for clock and data and three
other lines for power, ground and the programming
voltage. This allows customers to manufacture boards
with unprogrammed devices and then program the
microcontroller just before shipping the product. This
also allows the most recent firmware or a custom
firmware to be programmed.
For the various programming modes, see the
programming specification
28.9 In-Circuit Debugger
When the DEBUG Configuration bit is programmed to
a ‘0’, the In-Circuit Debugger functionality is enabled.
This function allows simple debugging functions when
used with MPLAB^® IDE. When the microcontroller has
this feature enabled, some resources are not available
for general use. Table 28-5 shows which resources are
required by the background debugger.
TABLE 28-5: DEBUGGER RESOURCES
I/O Pins:
RB6, RB7
Stack:
Two levels
Program Memory:
512 bytes
Data Memory:
10 bytes
To use the In-Circuit Debugger function of the micro-
controller, the design must implement In-Circuit Serial
Programming connections to MCLR/RE3, VDD, VSS,
RB7 and RB6. This will interface to the In-Circuit
Debugger module available from Microchip or one of
the third-party development tool companies.
DS39977F-page 482
 2010-2012 Microchip Technology Inc.