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G90 S-RAM problem

post #1 of 20
Thread Starter 
So, three days later, and more tea than I should drink - I have finally traced one of my G90 YA board problems to IC333 - the replacable user data battery s-ram. I have two of these chips - one works, the other gives an 89 error message. Is there any way to rewrite this chip - and if not, what's to do? Any suggestions would be graciously appreciated! Best - Ed
post #2 of 20
You mean the system firmware? I had this error you can re-write the information using the software that I gat to KAL it's on Curtpalme.com. You need the software, a serial null cable and a pc to do it with.
post #3 of 20
Thread Starter 
Don:
It doesn't seem to be system firmware that is corrupted. It is the chip that contains info on tube usage and user set-up. I've reloaded the firmware to no avail. Is there a battery that needs replacing somewhere? Best - Ed.
post #4 of 20
No Ed,

THe IC333 (Dallas DS1245Y-120) is a using a self powered system with an embedded Lithium battery : no way to change the battery 'cause it's within the device .

You can try to read the good one using a programmer device and copy this 'good' content to the wrong one (the one which generate error 89 today). However, if the chip embedded battery is low on this device, this will not solve your problem (no more data retention). Then, if it's the battery, you need to find a new Dallas DS1245Y-120 chip elsewhere (maybe I've got some, have to check ).

You can also try to make a clean SRAM data reloading using the S202 switch on YA and the procedure described inside the service manual in the relevant section.

Hope this help ?

John
post #5 of 20
Thread Starter 
John:
I just checked info on the lithium back-up battery on the IC333 chip. It has a 10 year life, which may explain why so many folk are suddenly having 88 and 89 errors.
If you - or anyone else - could burn me a new chip, I would be forever indebted to you, and would gladly pay costs incurred. SONY wants 170$ for the 20$ chip (heavy sigh). Best - Ed
post #6 of 20
Hello Ed,

Have to check that my H/W programmer can process this special memory device (it's in fact a pure SRAM with only a 3V battery in it). If yes, I can help you to program this chip .

The main issue is that you have to find a brand new DS1245Y-120 chip that is not 10 years old (manufacturing date ) : are you able to find such ??

Indeed, I'm pretty sure that my own DS1245Y chips are almost 10 years old ...

John
post #7 of 20
Ahhh, brings back memories of old E-home ECP's spitting out Dallas chips, all in about the same time frame.

Chip
post #8 of 20
Thread Starter 
John:
The chips are readily available, and according to the spec sheet, the battery is "turned on" for the first time when the chip is powered on for the first time, so your unused chips may still be fine. Sometimes, things work for the better. E.
post #9 of 20
You're right Ed,

I found DS1245Y-120 chips available from RS-component (at 49.9 or 65$ each ). I've checked my parts and unfortunatly these are DS1235 so smaller memory size ...

How can you manage the fillin' of a brand new DS1245Y-120 SRAM chip if you can't recover your G90 original data since they are now corrupted ?

John
post #10 of 20
Thread Starter 
John:
I have two G90s here - one of which I plan to sell if I can get the other working properly. I therefore have two IC333 chips, and should be able to crib off of the one that works (I hope - is the SRAM data unique to a given machine?).
In any case - I left the machine alone for two days, and was able to get the bad SRAM chip to work, but it is definitely corrupted - gives an "OVERCORRECTION" statement on the opening white screen (whatever that means...).
A little learning is a dangerous thing. E.
post #11 of 20
OK Fine Ed,

Then if we dump your working DS1245Y chip to copy its content to another 'new' chip to replace the defective one on your second G90 unit, then you'll loose all the second unit specific information such as its unique serial number, chassis and tubes timers and so on ... Could be an issue for your futur G90 buyer !

John
post #12 of 20
Thread Starter 
John:
Ah - but that's why I'll sell that unit, and keep the new chip. E.
post #13 of 20
OK Ed,

I've checked my DATAIO SPRINT Programmer and DS1245Y chip is in its database. I just need to re-install the PC that was dedicated to the programmer (HDD system crashed some time ago ...)

John
post #14 of 20
John / Ed

I have a g90 from 1999. It works fine but is this something that is going to fail or is this uncommon? all batteries have limited lives but did they really design something to only last 10 years?

I ask b/c if your burning new chips maybe we can burn and buy a few extras for future need.

steve
post #15 of 20
Quote:
Originally Posted by SPH View Post

John / Ed

I have a g90 from 1999. It works fine but is this something that is going to fail or is this uncommon? all batteries have limited lives but did they really design something to only last 10 years?

I ask b/c if your burning new chips maybe we can burn and buy a few extras for future need.

steve

Good point. I would like a spare too.....just in case.
post #16 of 20
Thread Starter 
Folk:
As I understand the data sheets....
The lithium battery backup has a nominal lifespan of 10 years, and only operates when supply voltage (ie. the G90) is turned off. In my case, I have a G90 which was made in 1999, and has a total of 70 hours on its chassis. The lithium battery was thus operational for most of its life, and is now suffering the pangs of old age. This may not be the case of a machine that has been used extensively over its lifespan.
Hope this alleviates some fears...
The spec sheet also suggests that the chip goes into a dormant state when supply power falls below a certain value. It may therefore be possible that the basic data stored on the chip may still be good, despite the fact that it cannot be accessed or overwritten by the G90 programming. This, at least, is my hope - and we'll just have to see once the chip is copied.
On that account, John - I've ordered two chips for 20$ each, and have found a local fellow at Union College who may be able to read and burn them. I'll let you know if it works shortly! Best - Ed
post #17 of 20
Quote:
Originally Posted by glassact View Post

On that account, John - I've ordered two chips for 20$ each, and have found a local fellow at Union College who may be able to read and burn them. I'll let you know if it works shortly! Best - Ed

OK Ed, it's easier for you to use local programmer tool/people than to send me the chips in France But in case of something goes wrong I can still do it for you if you'll need it.

All, as SPH point, that is indeed a good idea to save our Dallas chip memory content and keep this content in a safe place just in case if this content loose will happen (sooner or later ). I will do it for my two G90 units The only problem is that NOT all G90 owners can afford Dallas chip memory dump and save as this task requires special tools and skills to do so ... What can be done about this ??

John
post #18 of 20
what about make 10 copies and sell to others for "insurance"
post #19 of 20
Sorry you can't do that jeff,

Every single DS1245Y chip have specific unit relevant data in it (including unit S/N, timers and every custom registration/MG focus and [1-10] video memories datas). So you need to make a copy of each individual chip if you wanna keep your own unit infos

All, as Ed pointed, when the G90 unit is in Standby mode (red led at the back of the unit lit) then almost the complete YA board is powered, so IC333. Then, as long as your G90 unit stays in Standby mode, the IC333 lithium battery is NOT used (then you save years of data backup on this chip ).

The problem can come if the unit is completely switched off for years

John
post #20 of 20
Thread Starter 
John:
True, the worst case scenario is a G90 sitting unused for years. However, unless one leaves the unit on stand-by all the time, the battery will run out sooner or later. Given that my set is the canary in the coal mine, a G90 with 7000 hours on the clock will only last for a year or so longer before it shows signs of battery depletion.
Unfortunately, it appears that the Lithium backup battery is not recharged when the G90 is operating. It is simply is not used, suggesting that the day of battery demise is retarded, but not avoided if the projector is used often.
Please don't shoot the messenger. E.
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