SDRAM board

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

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

Sorgelig
Atari God
Atari God
Posts: 1507
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
Atari God
Atari God
Posts: 1507
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
Atarian
Atarian
Posts: 4
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
Retro freak
Retro freak
Posts: 11
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
Atari God
Atari God
Posts: 1507
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
Retro freak
Retro freak
Posts: 11
Joined: Mon Oct 16, 2017 8:39 am
Location: Germany

Re: SDRAM board

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

Thanx


Return to “MiSTer”

Who is online

Users browsing this forum: No registered users and 2 guests