4 Advanced Code Security Features in 8-bit PIC Family Microcontrollers

The 8-bit PIC microcontrollers, including the PIC18-Q24 family, introduce additional advanced code security features, such as PDID and SAFLOCK. These features are designed to inhibit unauthorized access to the microcontroller memory, thereby safeguarding the proprietary application firmware and the data stored within the memory.

Table 4-1 provides an overview of the advanced code protection settings on 8-bit PIC microcontroller memory sections.

Table 4-1. Overview of Advanced Code Security Features on 8-bit PIC Microcontroller Memory Sections⁽¹⁾
Memory Region	Memory Section	Applicable Advanced Protection	Associated Configuration Bit	ICSP Access⁽²⁾		CPU Access
Memory Region	Memory Section	Applicable Advanced Protection	Associated Configuration Bit	Read	Write	Read	Write
Program Flash Memory	Boot Block	PDID	ICSPDIS	No	No	Yes	Yes
	Application Block	PDID	ICSPDIS	No	No	Yes	Yes
	SAF Block	PDID SAFLOCK⁽³⁾	ICSPDIS SAFLOCK	No	No	Yes	No⁽⁴⁾
	User ID	PDID	ICSPDIS	No	No	Yes	Yes
Data Flash Memory	Data EEPROM	PDID	ICSPDIS	No	No	Yes	Yes
Configuration Bytes	Configuration Bytes	PDID	ICSPDIS	No	No	Yes	Yes
Device Configurations	DIA	PDID	ICSPDIS	No	No	Yes	No
	DCI	PDID	ICSPDIS	No	No	Yes	No
	Dev ID	PDID	ICSPDIS	Yes⁽⁵⁾	No	Yes	No
	Rev ID	PDID	ICSPDIS	Yes⁽⁵⁾	No	Yes	No

Note:

The code protection and write protection settings are disabled.
Limited ICSP read access will be enabled in the form of commands through the ISCPEN setting. Refer to the "Restricted Access to ICSP Interface" section.
The SAFLOCK feature is only applicable to the configured SAF area. Once SAFLOCK is enabled, the SAF area cannot be reduced.
Self-write operations through NVM functions are prohibited.
Dev ID and Rev ID can still be read using the dedicated ICSP commands. For more details, refer to the PIC18-Q24 Family Programming Specification.

This section provides more details about the advanced code protection features, their use cases and configuration through MPLAB® Code Configurator (MCC).