Abstract: A method, referred to as the interactive memory mapper or IMM (322), allows a user to program a memory (9) of a data processor (14) using a computer terminal (12) as a visual interface. The IMM allows a user to view and modify a pictorial representation of a data processor's memory space. When the IMM is utilized to allow the plurality of memory blocks to be viewed on the computer terminal, each block has visible attributes corresponding to the memory located at a memory address. Each of the plurality of memory blocks may be selected using a pointing device or keyboard and the blocks' attributes may be modified via an auxiliary controls subroutine (90) of the IMM program. The selected blocks may be created, moved, and resized to either add or subtract additional memory space, but is constrained to legal configurations determined by the specification of the data processor.

Abstract: A program (818) utilizes a functional description of a data processor to verify that the operations requested by the user are valid in the current context of the development environment (10). The program performs each of these functions by checking both physical (820) and contextual rules (838) stored in a memory (9). The program ensures that registers and memory in the data processor cannot be illegally configured and, therefore, fewer programming errors will occur during the development stages of a new data processing system.