21 System Register Block

The System Register (SYSREG) block is an array of system-level registers that contain user configuration information used to configure the microcontroller subsystem (MSS). The contents of these registers are initially set based on the information entered using the MSS configurator in the Libero software. The power-up initialized state of these registers, as well as write protection bits are controlled by flash configuration bits. The configuration bits are set during device programming.

The SYSREG block is connected to the AHB bus matrix and can be accessed by all bus masters. Write access to these registers provides the capability to modify the initialized SYSREG block register contents by the user application. There are seven types of System Registers as described in Table 21-1 which provide different levels of read/write access by bus masters.