26.1 Overview

The Peripheral Access Controller provides an interface for the locking and unlocking of peripheral registers within the device. It reports all violations that could happen when accessing a peripheral: write protected access, illegal access, enable protected access, access when clock synchronization or software reset is on-going. These errors are reported in a unique interrupt flag for a peripheral. The PAC module also reports errors occurring at the client bus level, when an access to a non-existing address is detected.

Note:
  1. The modules attached to the PB-PIC bridge and wireless subsystem as well as RTCC, DSCON, PUKCC and ICM are excluded from the PAC. The protection mechanism described in the System Configuration Registers (CFG) protects critical system registers (see System Configuration Registers (CFG) from Related Links).
  2. Traditional Peripheral Access Controller (PAC) documentation uses the terminology “Master” and “Slave”. The equivalent Microchip terminology used in this document is “Host” and “Client”, respectively.