SDRAM board

https://github.com/MiSTer-devel/Main_MiSTer/wiki

Moderators: Mug UK, Zorro 2, Greenious, spiny, Sorgelig, Moderator Team

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Sun Dec 31, 2017 7:09 am

cavemanxzx wrote:I think the Ramchip is bad.

Soldered by myself. No shortcuts.

ZX: black Screen on startup. when injecting a TAP some graphic corruptions.

I remember what memtest doesn't check - byte access! It only check full 16bit read/write.
So, check DH/DL (DQMH/DQML) signals - they are on arduino 3-pin header.

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Mon Jan 08, 2018 5:12 am

Today i've soldered SDRAM XS module with 64MB SDRAM chip AS4C32M16SB-7TCN. And it passes 160MHz! Even on 167MHz it produces only 4 errors in 30 mins. Although it's 7ns chip.
There is really some magic in Alliance Memory chips!

some time ago i've tried other 64MB chip - ISSI IS42S16320D-6TL. Although it's marked as 6ns, it passes only 130MHz test. The only difference - it's standard v3.1 board, not XS. But i'm sure it will be around the same on XS too.

hlide
Retro freak
Retro freak
Posts: 13
Joined: Sun Nov 05, 2017 8:06 pm

Re: SDRAM board

Postby hlide » Sun Jan 14, 2018 7:51 pm

That reminds me that topic on another forum about TerribleFire TF530. There were attempts to use ISSI chips instead of Alliance ones because of their prices. But they are tough to use and quite fussy about timings. Eventually, the author was able to use them after he found out the issue with faster SRAM.

THaase
Atari freak
Atari freak
Posts: 59
Joined: Mon Oct 16, 2017 8:39 am
Location: Germany

Re: SDRAM board

Postby THaase » Thu Feb 15, 2018 11:01 am

Sorgelig wrote:Today i've soldered SDRAM XS module with 64MB SDRAM chip AS4C32M16SB-7TCN. And it passes 160MHz! Even on 167MHz it produces only 4 errors in 30 mins. Although it's 7ns chip.


Dear Sorgelig,
can you please release the 160MHz Test also?
Inside of the git there are only tests for 150MHz and 167MHz.

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Thu Feb 15, 2018 1:30 pm

ok. released.

THaase
Atari freak
Atari freak
Posts: 59
Joined: Mon Oct 16, 2017 8:39 am
Location: Germany

Re: SDRAM board

Postby THaase » Thu Feb 15, 2018 2:17 pm

Thanx

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Sat Mar 17, 2018 5:57 am

I found another SDRAM chip with the same achieved speed. It's Winbond W9825G6KH-6.
Surprisingly it's much cheaper than AS4C. So, now we are more safe having alternative.

JimDrew
Atari Super Hero
Atari Super Hero
Posts: 667
Joined: Mon Nov 04, 2013 5:23 pm

Re: SDRAM board

Postby JimDrew » Mon Mar 26, 2018 11:25 pm

Nice. I will try some of these. My boards are all passing the 167MHz. These are the small board that requires the technical build.
I am the flux ninja

olin
Atari freak
Atari freak
Posts: 54
Joined: Tue Nov 21, 2017 8:57 pm

Re: SDRAM board

Postby olin » Wed Mar 28, 2018 8:51 pm

Sorgelig wrote:I found another SDRAM chip with the same achieved speed. It's Winbond W9825G6KH-6.


OK, that supports my find of w9825g6jh-6 I wrote earlier in DE0-ns thread. JH seems to be obsolete by now though, so KH might be its successor. By trial in my conditions the w9825g6jh-6 is less affected by the PLL shift (ie. is more tolerant to different values of PLL shift) than AS4C.

User avatar
cvenditti
Atari freak
Atari freak
Posts: 74
Joined: Sun Nov 19, 2017 12:45 am

Re: SDRAM board

Postby cvenditti » Sat Mar 31, 2018 1:33 pm

Yesterday I tried the new memtest for the first time with a batch of new boards, the results are not consistent with the old memtest. I had lots of errors with the old memtest_167MHz and memtest_160MHz just after 1 minute but I had none with the new memtest even after 15 min at 167MHz.
Can someone else please do the same test and see if they have the same results?
Last edited by cvenditti on Sat Mar 31, 2018 2:36 pm, edited 1 time in total.

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Sat Mar 31, 2018 2:19 pm

167MHz is extreme frequency. Results on this frequency highly depend on many factors. Even passing on one DE10-nano board won't exactly will pass on another DE10-nano.
New memtest uses variable memory frequency so, code is different and thus produces slightly different result than single-freq memtest.
150MHz pass is more than enough. There are no cores using frequency higher than 128MHz.

User avatar
cvenditti
Atari freak
Atari freak
Posts: 74
Joined: Sun Nov 19, 2017 12:45 am

Re: SDRAM board

Postby cvenditti » Sat Mar 31, 2018 2:43 pm

They all passed the old memtest_150MHz and I understand that is more than enough. But which test (between the old and new) do you consider the most accurate (Which one you will use to certify the frequency of the broads to buyers)?

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Sat Mar 31, 2018 4:55 pm

Both are OK.

bluescrn
Atarian
Atarian
Posts: 1
Joined: Fri Mar 23, 2018 8:02 pm

Re: SDRAM board

Postby bluescrn » Sat Mar 31, 2018 5:44 pm

Took me 3 attempts (as a complete newbie to SMD soldering, using a very basic soldering iron) to assemble a working extra-slim board, but I appear to have just succeeded, and have a functioning MiSTer setup!

First attempt - solder joints under the RAM chip weren't flat enough, didn't realise until I'd started soldering the RAM. Oops.

Second attempt - not really sure, can't spot any really obvious problem - maybe this board is salvageable, or maybe I fried the chip by applying too much heat while trying to get rid of solder bridges...

Third attempt - thought it was going to go the same way as the second, somewhat messy job soldering the chip and cleaning up solder bridges... but this one's been running the 167Mhz test for the last 20mins or so with no errors - hooray!

Fairly challenging to put together if you only have very basic soldering gear+experience... but it's possible. Just be prepared to write off a couple of boards/chips in the process...

User avatar
cvenditti
Atari freak
Atari freak
Posts: 74
Joined: Sun Nov 19, 2017 12:45 am

Re: SDRAM board

Postby cvenditti » Wed Apr 04, 2018 12:45 am

I received some Winbond W9825G6KH-6. (lcsc.com is not packing as well as Digikey but they are definitely cheaper)

IMG_20180403_191801068.jpg


I tried in a XS board, it is performing fine, like a AS4C16M16SA-6TCN

IMG_20180403_202614421.jpg


Can someone please update the WIKI page to added the W9825G6KH-6 as a choice along with the AS4C16M16SA-6TCN:
https://github.com/MiSTer-devel/Main_Mi ... embly-(DIY)

Thank you
Cyril
You do not have the required permissions to view the files attached to this post.

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Wed Apr 04, 2018 1:21 am


JimDrew
Atari Super Hero
Atari Super Hero
Posts: 667
Joined: Mon Nov 04, 2013 5:23 pm

Re: SDRAM board

Postby JimDrew » Thu Apr 05, 2018 11:59 pm

I received 200 of these chips today (I already had the boards). They will be available shortly on my website.
I am the flux ninja

eris
Retro freak
Retro freak
Posts: 11
Joined: Fri Apr 06, 2018 11:32 pm

Re: SDRAM board (cap substitution)

Postby eris » Fri Apr 06, 2018 11:57 pm

I'm trying to acquire all the parts for a MiSTer. The first thing I looked for was the surface mount caps for the memory board.

KEMET C0805C104J5RACTU

Unfortunately everyone seems to be out of them right now unless I want to buy 4000.

I looked on mouser and there's a very close match made by KEMET, but it's an automotive part with flexible contacts and it's 3x as expensive as the original.

Any suggestions for substitutions?

thanks,

iris

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Sat Apr 07, 2018 12:16 am

Any capacitor of 0805 footprint with same value will be OK.

User avatar
cvenditti
Atari freak
Atari freak
Posts: 74
Joined: Sun Nov 19, 2017 12:45 am

Re: SDRAM board

Postby cvenditti » Fri Apr 13, 2018 2:34 pm

$4 Coupon for your first order at https://lcsc.com/ for the W9825G6KH-6 https://lcsc.com/product-detail/RAM_W98 ... 62246.html
FIRSTORDER4

THaase
Atari freak
Atari freak
Posts: 59
Joined: Mon Oct 16, 2017 8:39 am
Location: Germany

Re: SDRAM board

Postby THaase » Wed Apr 18, 2018 7:58 pm

Dear Sorgelig, dear cvenditti,

have I missed some additional change (capacity or something) needed for the Winbond?
I've tried 4 of them on the XS board till now - none is working.
To be shure that it's not because of the boards I've reworked the boards with the AS4C16M16SA-6TCN and they are performing well with 167MHz.

So anybody an idea what I'm doing wrong?
(I've totally no problems with the AS, but the Winbond don't like me - it seems)

User avatar
cvenditti
Atari freak
Atari freak
Posts: 74
Joined: Sun Nov 19, 2017 12:45 am

Re: SDRAM board

Postby cvenditti » Wed Apr 18, 2018 8:10 pm

Sorry to hear that THaase, but so far I did 3 XS and 3 Regulars they all did work fine.
I used the same caps that for the AS4C16M16SA-6TCN.

Where did you buy them (LCSC.com)?
Did you try the old mem. test (start with the 140Mhz).
Is the IC in the right orientation (it is unlikely that you did that 4 times :wink: )

Sorgelig
Fuji Shaped Bastard
Fuji Shaped Bastard
Posts: 2035
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: SDRAM board

Postby Sorgelig » Thu Apr 19, 2018 2:59 am

THaase wrote:I've tried 4 of them on the XS board till now - none is working.

How it doesn't work? Does it need to pass exactly 167MHz?

THaase
Atari freak
Atari freak
Posts: 59
Joined: Mon Oct 16, 2017 8:39 am
Location: Germany

Re: SDRAM board

Postby THaase » Thu Apr 19, 2018 4:52 am

Sorry to miss some important informations and thanks for the help already.

@cvenditti:
Got the form LCSC (just 12 pcs - for first test) - packed in tray - so I don't think that they have been damaged during transport.
I've only tried new memtest .... but should make no difference.
Right orientation? YES - one time, maybe ... 4 times (I'm not Homer Simpson :-) ) - NO - I've checked this, belive me.

@Sorgelig:
No, the even not pass 70MHz :-( (automatic test dropping to 70MHz and error couter is running wild - manual -> same)

I have no real idea bout the problem.
Having EDS protected soldering place.
Using different methods of soldering (hotair and drag) (sorry no reflow available).

What I can say: No problems with the AS - I've only one board XS with passing 140MHz, all other doing 167MHz.
The universals one passing in most cases 160MHz (new test) and at least 150MHz.
So I don't think that it's caused by my soldering skills ....

I can also eliminate the boards - as I said: Having Winbond soldered - don't work at all .... removing the Winbond (hotair), cleaning pads and soldering AS ....
-> passing 167MHz.

I don't have any idea anymore yet - execpt:
1.) Got some damaged chips (either transport, picking, whatever)
2.) They need some other capacity (not to be expected - but who knows - the reson why I'm asking)
3.) They've problems on XS board (but cvenditti did also XS)
4.) I'm doing something constantly wrong (but I don't have any idea what it should be)

Thanks for your help.
The Winbond are not available at LCSC at the moment (placed order yesterday) and I've to place an order at Digikey anway - I'll go for some more AS

Thanx!

THaase
Atari freak
Atari freak
Posts: 59
Joined: Mon Oct 16, 2017 8:39 am
Location: Germany

Re: SDRAM board

Postby THaase » Thu Apr 19, 2018 4:53 am

** deleted *** double post


Return to “MiSTer”

Who is online

Users browsing this forum: No registered users and 4 guests