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Re: Interfacing Axis to 8/16 bit device




Hi,

the be0 to be2 can be used together with the SRAM chip selects
csr0 and csr1 in the way you describe. You will have to enable
the common write enable mode (sram_type field in R_BUS_CONFIG).
Only the csr0 and csr1 chip selects can be used, no other.

Per Zander

On Tue, 6 May 2003 John_Pham@xxxxxxx.com wrote:

> Can be0, be1, be2, and be3 be use in selecting which byte from the 
> peripheral chip - assuming I'm  interfacing to a 16/8 peripheral 
> and need sometimes to get the high byte or low byte.  Or is be0..be3
> strictly for dram access?
> 
> here's the bus access function
> io write
> func mode /cs  /uds  /lds    r/w       d[15:8]   d[7:0]
>   standby  H    x      x      x          x         x
>   byte     L     H     L      L          x         odd byte
>            L     L     H      L         evenbyte   x
> word acc   L     L     L      L         evenbyte   odd byte
> 
> io read
>   standby  h     x     x      x          high-z     high-z
>   byte     L     H     L      H          invalid    odd byte
>            L     L     H      H          even byte  not valid
>   word     L     L     L      H          even byte  odd byte
> 
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