DIY: new cell for NVRAM chip

karlm · Post by **karlm** » Mon Jun 12, 2006 11:03 pm

Paolo -

First, register with Maxxim and get an account. Then, so a search for the DS12887A. Somewhere on that page you can 'order', you can 'order' up to two 'samples' that you can use for engineering/prototyping purposes.

Note: Only some chips are 'free samples'.

If anyone is really stuck, send me a pm with your maxxim username/login and the address you want the chips sent to.

cheers

karlm.

Post by **ggn** » Tue Jun 13, 2006 8:06 am

Just placed an order for free samples! (crosses fingers

)

Paolo · Post by **Paolo** » Wed Jun 14, 2006 5:00 pm

PM sent.
But maybe I misunderstood your post.

By the way, I never received the chips, and I am not sure I can re-order them...

Muphex · Post by **Muphex** » Thu Jul 20, 2006 6:22 pm

What lovely people at Matrixx, they sent me the sample so I can now replace my RTC. Rather brilliant of them aswell. I used the company name that I occassionally trade under that is clearly found on the internet as a web design company so they must have known that they were for personal use!

Paolo · Post by **Paolo** » Tue Sep 05, 2006 10:02 pm

Well, guys. My NVram died on me!
And I don't have the replacement chip since it never arrived from maxim

Now I can't even correctly boot from HD.

I don't know if start cutting my chip's top (since it is going in the trashbin anyway) to replace the cell battery, or just wait a little more.

Ah, well...

Post by **[ProToS]** » Tue Sep 05, 2006 10:18 pm

another exemple from Didier Mequignon (aniplayer, ct060 tos etc .. coder)

karlm · Post by **karlm** » Tue Sep 05, 2006 10:50 pm

go here people, and do the search for the chip

https://shop.maxim-ic.com/storefront/welcome.do

cheers

karlm

Paolo · Post by **Paolo** » Wed Sep 20, 2006 9:41 pm

WOW!
My second request has been fulfilled.
These are 12887 chips.
NOT A
Not A+

I understood that the + is about some recycling stuff, but what is the A about?

May I use this chip?

karlm · Post by **karlm** » Thu Sep 21, 2006 11:44 pm

bugger

something should hit your postbox soon Paolo.

As for the A version, I think the A means that the NVRAM can be flashed clear, in the spec sheet it says:

RAM Clear Function (DS12885, DS12887A, and DS12C887A)

So I'm assuming the non A version needs to be cleared another way. Seems weird though, but would be used in situations where you don't want the NVRAM getting wiped.

Cheers

karlm.

karlm · Post by **karlm** » Sun Oct 15, 2006 10:24 pm

just for those having trouble finding the chips at Maxxim

http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2680

cheers

karlm.

DarkLord · Post by **DarkLord** » Mon Oct 16, 2006 4:32 pm

Just thought I'd mention this, for those who are like me, not very
technically advanced with a soldering iron...

I sent my Falcon MB to Alex Yu at ATY Computers here in the US,
and for about $40, he replaced the dead clock chip with a socket,
so that I can replace the clock chip/battery myself, anytime it goes
dead, from now on.

samf · Post by **samf** » Mon Oct 16, 2006 7:43 pm

DarkLord wrote:Just thought I'd mention this, for those who are like me, not very
technically advanced with a soldering iron...

I sent my Falcon MB to Alex Yu at ATY Computers here in the US,
and for about $40, he replaced the dead clock chip with a socket,
so that I can replace the clock chip/battery myself, anytime it goes
dead, from now on.

That's great news Darklord. I didn't even know they were still in business!
BTW, where in the USofA do you live?

I live in Virginia and I think I'm the only Atari Falcon owner in my area.

DarkLord · Post by **DarkLord** » Mon Oct 16, 2006 9:03 pm

samf wrote:
DarkLord wrote:Just thought I'd mention this, for those who are like me, not very
technically advanced with a soldering iron...

I sent my Falcon MB to Alex Yu at ATY Computers here in the US,
and for about $40, he replaced the dead clock chip with a socket,
so that I can replace the clock chip/battery myself, anytime it goes
dead, from now on.
That's great news Darklord. I didn't even know they were still in business!
BTW, where in the USofA do you live?

I live in Virginia and I think I'm the only Atari Falcon owner in my area.

Yep, Alex is still around. I keep him in business correcting all my mistakes.

He has a website, check it out sometime:

http://www.atycomputer.com/

I'm not all that far from you - I live in Prestonsburg, KY. There is another Falcon owner between us, I know for sure. His name is Barry Shortridge, AKA "Phantomm". He lives in Mouthcard, KY and we converse all the time. You'll see his posts in the Atari newsgroups occasionally. Really nice guy.

Catch ya later.

Post by **[ProToS]** » Wed Mar 28, 2007 1:18 am

a french article guide to nvram remplacement by Slyfox

http://christophe.bray.free.fr/informat ... /index.htm

Dew-It · Post by **Dew-It** » Wed May 02, 2007 5:53 am

karlm wrote:just for those having trouble finding the chips at Maxxim

http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2680

cheers

karlm.

Thanks Karlm hope i get the the chips.

Was'nt sure what to put there for a company, so I put Atari Repairs. How many pins is the socket?

karlm · Post by **karlm** » Thu May 03, 2007 10:13 pm

socket? You'd have to solder in a 24pin DIL type, as you can see from the picture above, it's soldered directly to the motherboard.

cheers

karlm.

Dew-It · Post by **Dew-It** » Fri May 18, 2007 10:13 pm

karlm wrote:socket? You'd have to solder in a 24pin DIL type, as you can see from the picture above, it's soldered directly to the motherboard.

cheers

karlm.

Sorry
I meant how many pins was the ic, which you answered above. Which is 24. So when I need to change the RTC, probably won't even be messing around with a Falcon for another ten years, but on never knows. I would rather solder in a 24 pin socket, then a ic. Which Darklord had done to his Atari Falcon computer by ATY computer

Dew-It · Post by **Dew-It** » Sun May 20, 2007 1:52 am

I decided to have Alex Yu install the socket for me. Just to hard for me to remove a soldered IC on the mainboard of the Falcon.

FatRakoon · Post by **FatRakoon** » Fri Aug 31, 2007 3:15 am

Can I just butt-in here you lot...

On the picture that ProTOS has so kindly offered us, on the right/hand side, we can see the wires soldered for the battery yes? - Which is Positive? - the top I am assuming.

Ok, whats the thing on the left of it? what is that component?

Sorry If I am missing what it is, but I just went to have a look at my Clock chip and I moved the top bit with my finger and thumb and it fell off????

Im not entirely convinced it was even connected?????

retinal scan · Post by **retinal scan** » Sun Dec 30, 2007 11:51 pm

FatRakoon wrote:Can I just butt-in here you lot...

On the picture that ProTOS has so kindly offered us, on the right/hand side, we can see the wires soldered for the battery yes? - Which is Positive? - the top I am assuming.

Ok, whats the thing on the left of it? what is that component?

Sorry If I am missing what it is, but I just went to have a look at my Clock chip and I moved the top bit with my finger and thumb and it fell off????

Im not entirely convinced it was even connected?????

Hi there, it's my first post on here but I have some info for you FatRakoon -

The cylindrical object you see on the left of ProTOS's photo is the metal can containing the clock chip's crystal. This is connected to the rest of the device (lower part of the 24 pin package) by the very thin wires seen on the extreme left.

The stubs on the right of the chip are the battery + & - terminals, the old battery is/was housed next to the crystal in the upper portion of the package.
The terminals are indeed: upper +, lower -
I have just completed my version of this mod - which started off similar to your experience with the chip so far.

Unfortunately I think you may have ruined your chip by removal of the upper part of the package, breaking the connections for the crystal.
The battery terminals are OK to cut as long as there is enough copper to solder wire to for a new battery.

I started by trying to cut off the top 1mm of package as advised elsewhere for this mod. My chip package seems to be similar to ceramic so I had a lot of problems getting into the battery compartment. Long story short - I accidentally prised off the right hand side of the upper section, cutting the battery terminals completely. There was enough exposed copper fortunately to solder a couple of very thin single core wires onto them.
It took me 5/6 attempts to get the solder to stick, but eventually it worked.

Use a CR2032+holder, soldered to the other end of these wires, soldering directly to a cells terminals is difficult and could be dangerous.

As long as you insulate the conducting parts of the mod, you can secure the cell somewhere convenient.

I am waiting for my camera to recharge so I can upload the photos for you. I will see what I can do. (see http://www.atarimad.co.uk)

You may need to source yourself a new chip but for 11-12 GBP you can get a replacement DS12887 from Farnell - I can't say if it will work for you but it's worth a try!

Steve

FatRakoon · Post by **FatRakoon** » Mon Dec 31, 2007 12:58 am

Hiya there mate.

Exactly 4 months eh?

Seriously though, I have ended up swapping the CHIP for a socket, and yes, I have sourced a pair of new Maxim Chips and they have done the job.

One small issue I have, is that one of the legs has bent over on the socket and is not actualyl soldered to the board at all... This has pissed me off, however, it does not seem to have affected it enough for me to worry about... In that I mean, that the year is NOT kept, but nor is a couple of things in the CT63 options... It wont save the boot order, so it always tried IDE1 then IDE0 and takes ages therefore to boot from SCSI, but these are all minor irritations - the year for example is somehting that Im sure we all have an issue with and there are other fixes just I dont have one myself.

Anyway, what I am saying is that its now done.

Many thanks for the info however.

Post by **Dal** » Mon Dec 31, 2007 1:40 pm

Just ordered my free sample chip under the pseudo company name Daltech lol. I'll probably opt for soldering a socket, then installing the new chip. Once that's all working, I'll hack the old chip with the CR2032 mod so it's future-proof.

Post by **Dal** » Thu Jan 10, 2008 11:48 pm

My DS12887A arrived today. I'll solder in the socket I got from Maplins tomorrow and plug it in and see how it goes.

Post by **Dal** » Mon Jan 14, 2008 12:54 am

I have removed the old NVRAM IC and soldered in a socket and plugged in the new DS 12887A. First boot up was fine - I ran a program to set the NVRAM settings and then rebooted. The reboot never succeeded....

I hear the usual pop from the speaker as it starts up, but I keep hearing the pop every 3 seconds or so. Seems like the initialisation fails and the Falcon is trying again. I left it for about 5 minutes and still nothing comes up. I pulled the Dallas chip out again and tried booting without it with the same result.

I'm guessing that I may not have done the settings correctly but I'm not sure if I can physically reset the chip. Have tried booting with [CTRL]+[ALT]+[UNDO] held down a couple of times but nothing seems to be working.

Ideas anyone?!?

Desty · Post by **Desty** » Mon Jan 14, 2008 9:29 am

Dal_1978 wrote:The reboot never succeeded....

I hear the usual pop from the speaker as it starts up, but I keep hearing the pop every 3 seconds or so. Seems like the initialisation fails and the Falcon is trying again. I left it for about 5 minutes and still nothing comes up. I pulled the Dallas chip out again and tried booting without it with the same result.

"...Ohshitohshitohshit"

Atari-Forum

DIY: new cell for NVRAM chip

DIY: new cell for NVRAM chip

Re: DIY: new cell for NVRAM chip

NVRAM mod

HELP!!!

Re: HELP!!!