7 Configuration Bits

In dsPIC33AK128MC106 family devices, the Configuration Words are implemented as volatile memory. This means that configuration data will get loaded to volatile memory (from the Flash Configuration Words) each time the device is powered-up. There are two types of regions, CFGA for general purpose and CFGB for security. Both regions have a backup copy. The configuration data are automatically loaded from the Flash Configuration Words to the proper Configuration Shadow registers during device Resets. The locations of the CFGA and CFGB registers are shown in Table 7-2.

In the dsPIC33AK128MC106 family, the configuration and calibration data is duplicated in Flash for improved robustness. If a double ECC error is detected during the start-up sequence, the device will restart the loading of the calibration and configuration from the backup set in Flash. The backup addresses are offset 0x800 from their counterpart. When programming the Configuration bits, both the regular and backup sets should be programmed identically. Within the MPLAB IDE, only the regular set are configured. The backup set's duplication and programming is handled by the tool set.

To maintain the integrity of the stored configuration values, logic performs ongoing bit value checks. All device Configuration bits are implemented as a complementary set of register bits.