Texas Instruments CDT370, Руководство пользователя

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Memory Mapping
7-4
Register File Memory
Description Locations are part of the TMS370 on-chip register file.
Mapping Attributes It should be mapped as IRAM for location 0x00 to 0x7F
or 0xFF, depending on the device to emulate.
Peripheral Frame Memory
Description This type is used for 16-byte ranges in the peripheral register file.
Program ROM/EPROM Memory
Description This memory type is used for addresses that fall in the range of
the on-chip mask ROM. Program ROM and program EPROM are emulated
using the high-speed RAM in the emulator.
Mapping Attributes Program ROM should be mapped as emulator ROM,
and program EPROM should always be mapped as PEPROM. This means
that whenever internal memory is enabled on the device, memory accesses
in this range are satisfied by the emulator (just as if the memory were actually
on the chip).
You must not define any EPROM control frame (EPCTL) when you define
PEPROM. You can define only one PEPROM.
Protection Attributes Program ROM is, by default, write protected. Write
cycles to addresses in a range of this type cause an access violation trap to
occur. Writes to external target memory cause a trap, but the write operation
cannot be prevented.
Note: Unsupported EPROMS
Data EPROM (DEPROM) and Custom EPROM (CEPROM) are not sup-
ported.
Data EEPROM Memory
Description The data EEPROM type is used for addresses that fall in the
range of the chip data EEPROM. Some devices have no memory of this type
in the memory map. Data EEPROM is emulated using the RAM in the emulator
and a special interface logic that allows you to use all the data EEPROM mod-
ule features found in any TMS370 devices:
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Control frame access
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Write protection registers
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Write protect override mode
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Array programming
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Minimum programming time criteria