
ÉlanSC310 Microcontroller Evaluation Board User’s Manual
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DOS ROM/Application ROM Mapping
The application ROM space (also known as DOS ROM space) is selected by the
DOSCS chip select. Only 256Kx8 Flash parts are supported; 256Kx8 and
512Kx8 EPROMs are supported. JP12 selects between Flash/EPROM (1-2 = Flash,
2-3 = EPROM). JP13 selects between 256Kx8 and 512Kx8 parts (1-2 = 256K,
2-3 = 512K).
NOTE:
512Kx8 Flash can be supported after a minor board rework. Contact your
local AMD or distributor Field Application Engineer for more information.
Access to the application ROM begins at offset 0h, and extends up to 1FFFFFh,
depending on the size and number of parts installed. Application ROM is accessed
through the MMS windows.
It is also possible to access linear decoded application ROM. This requires setting
up ÉlanSC310 Index B8h. However, the processor must be set up to access memory
above the 1 Mbyte boundary.
BIOS ROM Mapping
BIOS ROM mapping is similar to application ROM mapping. BIOS ROM is
selected by the BIOSCS chip select. 128Kx8 and 256Kx8 Flash and EPROM
devices are supported.
Access to the BIOS ROM begins at offset 0h, and extends up to 3FFFFh, depending
on the size of the device. Typically the BIOS ROM is accessed through a linear
decode set up for the address range E0000h through FFFFFh. This is set up using
ÉlanSC310 Index register 65h. It is also possible to access the BIOS ROM using
pages in the MMS windows.
evalbd.book : ch4 Page 9 Thursday, August 8, 1996 2:34 PM