Nios II Classic Processor Reference Guide

ID 683620
Date 10/28/2016
Document Table of Contents The LIMIT Field

When the amount of memory reserved for a region is defined by an upper address limit, the LIMIT field specifies the upper address of the memory region plus one. For example, to achieve a memory range for byte addresses 0x4000 to 0x4fff with a 256 byte minimum region size, the BASE field of the mpubase register is set to 0x40 (0x4000 >> 8) and the LIMIT field is set to 0x50 (0x5000 >> 8). Because the LIMIT field is one more bit than the number of bits of the BASE field of the mpubase register, bit 31 of the mpuacc register is available to the LIMIT field.