8051 64K external SRAM possible?

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I'm planning to add some external SRAM to my 8051.
I've seen many examples how to add 32K but never 64K.
Is it possible to have the full external data space in SRAM?
If so, do I just hardwire the CE line to always select the
chip?

Thanks,
Andrew



Re: 8051 64K external SRAM possible?


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Of course.


Yes. ( and WRN -> WEN and RDN -> OEN )


Re: 8051 64K external SRAM possible?
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Yes there is no problem with using the full 64K for SRAM. The reason that
people often use 32K is that 32K chips are cheaper and secondly, it keeps some
memory space for mapping external peripherals such as A/D chips etc.

Re: 8051 64K external SRAM possible?
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I've done banking with 6811s with up to 1M of space.  Works well for
static kind of memory, but puts some trickery in the code.  Hopefully
your compiler supports it.

Re: 8051 64K external SRAM possible?
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Of course it is possible.  P0 and P2 give 16 address lines.  You are
adding XDATA which is 64K external data.  This is a seperate space to
the iData and Data. (though confusingly some 51]s have "internal xdata"
that is an additional space.)

There is a description of this in thje C51 Primer at
Http://Quest.phaedsys.org
 
 



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