Texas Instruments CDT370, User Manual

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Memory Mapping Introduction
7-2
7.1 Memory Mapping Introduction
The memory mapping capability of the TMS370 debugger allows you to spec-
ify exactly how the CPU is allowed to access various memory ranges. The
TMS370 device provides significant flexibility in the memory map, with its vari-
ous configurations of internal memory and external addressing capability. In
addition, the emulator has 64K bytes of high-speed emulation RAM, which can
be used to functionally emulate target system memory. The debugger memory
mapping system allows you to take advantage of the hardware’s flexibility.
Specifying the memory map is accomplished by dividing the 64K address
space into ranges. Each range starts and ends on a 16-byte boundary and has
a type that determines how addresses in the range are accessed. The type
determines:
-
what class of memory the range falls into, such as RAM, program ROM,
EEPROM, etc... (the type for a given range is determined by the architec-
ture of the particular TMS370 device being emulated),
-
whether the memory is to be accessed internally on the chip, from external
target memory, or from emulator RAM, and
-
the protection that allows you to prevent the CPU from reading and/or writ-
ing to the given address range.
Please refer to
Defining a Memory Map in the TMS370 Family C source De-
bugger User’s Guide for more information.
Any address that is not covered by a specified range in the debugger memory
map is considered to be “unconfigured”. All unconfigured memory is protected
against both read and write operations so that if the CPU tries to access an
unconfigured location, an access violation occurs, and the CPU halts.