Phytec kitCON-161CS, Руководство по оборудованию

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Memory Models
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PHYTEC Meßtechnik GmbH 1999 L-356e_2
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5 Memory Models
The C161x Controller provides up to five Chip-Select Signals at port
P6 for easy selection of external peripherals or memory banks. Two of
those Chip-Select Signals (/CS0, /CS1) are used internally.
Depending on the setting of jumper JP13 these Chip-Select Signals
select Flash bank 1 on U8/U9 and RAM bank1 on U10/U11. Flash
bank 1 houses a total memory of either 256 kByte or 1 MB whereas
RAM bank1 house memory devices of type 32 kByte, 128 kByte or
512 kByte within a SO28-32 package.
In order to use the Chip-Select Signals they have to be enabled during
reset. The assignment of the Chip-Select Signals to specific address
areas is done with the corresponding ADDRESELx and BUSCONx
register. Note that ADDRESELx has to be configured prior activating
of the Chip-Select Signal with BUSCONx. Take care that the memory
areas do not conflict.
Prior definition of the ADDRESELx and the BUSCONx register only
/CS0 is active in the entire address space and remains active for all
areas not assigned to an other Chip-Select Signal.
On the next page you will find two examples for configuring the
memory area. These examples refer to the standard configuration of
jumper JP13 (1+2, 3+4), i.e. /CS0 controls Flash bank1 and /CS1
RAM bank1. These examples match the needs of most standard
applications.