Crossware: MMU support to ARM debugger

Crossware, a embedded software tools developer, has added support for the ARM9 memory management unit (MMU) and fast context switch extension (FCSE) to its ARM Development Suite. This allows developers to exploit the advanced memory management features of ARM9 chips such as the Atmel AT91SAM9263 and Atmel AT91RM9200 microcontrollers. Full debugging is possible when the memory management unit is enabled even when complex virtual to physical memory translation is being used.

 The Crossware debugger understands the memory address translation process and can determine which physical memory is being used for different virtual addresses. Full debugging is also possible when the fast context switch extension is being used. The FCSE allows different processes to easily share the same memory space. The Crossware debugger knows which executable code belongs to each process and can select the appropriate debugging information even though the processes share the same execution address. Crossware's ARM simulator will also simulate the operation of the MMU and the FCSE. This enables code which uses these features to be tested on the developer's PC before being tested on the target hardware. It also allows developers to explore the operation of the MMU and FCSE without having any hardware at all.

 The complex memory organisation required when virtual memory translation is being used or when the fast context switch extension is in operation necessitates the use of a linker script to specify the detailed code and data layout of the target system. In order to simplify the process of creating the linker script, Crossware has added a drag-and-drop GUI linker script editing facility to its Embedded Development Studio. This allows the developer to rapidly create and modify linker scripts and therefore avoid the need for a detailed understanding of the linker script command language.