Re: How to configure MDREFR on StrongARM SA-1110

[Abraham vd M. <ab...@2d...>]

Hi Russell!

> > That's what I gathered. However in the SDRAM SPD (Serial Presence Detec=
t -
> > the little EEPROM which contains the info about the DIMM) module, the
> > refresh time goes from 3.9us up to 125us which is orders of magnitude
> > shorter than all the other refresh times I've seen.
>=20
> 64ms / 4096 =3D ~15us

Thanks. That clears it up.

One more question. You're currently ignoring the burst access times when
configuring MDREFR. Isn't that dangerous? (if you have any bursts, its going
to take too long to refresh and then the DRAM contents will corrupt) or am I
missing something?

Also, the SPD datasheet refers to SDRAM burst lengths of 1, 2, 4, 8 and full
page. Is that 1,2,4,8 clocks? What is a full page? Is that across all the
rows? Does it need multiple clock cycles to refresh a row (i.e. cas latency
* rows =3D=3D longs burst access?)

--=20

Regards
 Abraham

* netgod opens his mailbox and immediately wishes he hadnt

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 Abraham vd Merwe - 2d3D, Inc.

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