Hi Mark, et al.

--- In minimigtg68@yahoogroups.com, Mark McDougall <msmcdoug@...>
wrote:
> AFAIK there are two issues with (DE1) Minimig atm...
>
> (1) SDRAM timing. Some DE1 boards use different SDRAM chips which
aren't
> compatible with the Minimig SDRAM controller out-of-the-box. I also
believe
> that SDRAM problems can be mitigated to some extent via timing
constraints
> in Quartus.

The SDRAM controller files for v12d and v12e have one difference.
The SDRAM controller file for V13 reverts to using the 12d version.

FMAX setting for 13 is markedly different from either 12 versions.

SPIHOST.rom appears identical for 12 versions, but different for V13.
V13 spihost.rom still works for me when using 12d build.

Haven't looked too much at differences between other file versions.

My experience with different versions:

12d works fine, with versions: 7.1, 7.2, 8.0, 8.1 (all FULL versions)
12e builds fine, but always gives me a spihost load timeout error.

13 only works for me when built using 8.0 (sp0/sp1).
Blanks screen when built with 7.x , and I get the RED error screen
when built with 8.1 $%#!!! (I think ozkanocakli had the same problem).

I have the later SDRAM chip : PSC - A2V64S40CTP
I contacted TerASIC support, as the PSC web-site :
http://www.psc.com.tw/ doesn't provide any datasheets.
TerASIC support told me that data for the PSC chips is covered by an
NDA, but they believed the PSC chips were identical to the ISSI chips
(for which data is freely available).

I can only suspect that the chips are ever-so-slightly different, and
the SDRAM controller is running just within tolerance for ISSI chips,
but outside that of the PSC chips.

I did get this:
http://whoyouvotefor.info/altera_sdram.html
SDRAM controller working on my DE1 ok, might try grafting it on to
minimigtg68 over the xmas break.

> (2) Reportedly some SD cards aren't compatible with the Minimig SD
> controller. People have had success with some previously failing SD
cards
> using certain format utilities.

I haven't found an SD card that wouldn't work correctly *AFTER* being
formatted with SD card specific software. I mainly use Toshiba brand.

> Anyone else disagree with this summary?
A fair assessment.

Cheers,
Leslie