You are here

Just 20 Years

Page 1 of 2

Just 20 Years

PostPosted: Fri Aug 07, 2020 10:34 am
by where_theres_a_will_theres_a_way
I had an email from a friend in Spain about a Hammond XK2. The top C doesn't play when opening a bank (or something like that) but does the rest of the time.

So I thought, sounds like a software problem. Can it be that there is a bug... or...

So I checked the data sheet for the FLASH memory. It has "20 years retention" which is kind of what I remembered. XK2 was made 1999-2004 so that fits.

That got me thinking, how many other things are there out there, about 20 years old, that are about to exhibit strange behaviour?

Cars... old mobile phones... and of course all those lovely synths that people love to keep going. Just about everything that's made these days has some sort of processor built in and they all use FLASH memory.

Is this the new millenium bug waiting to happen!

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 11:30 am
by BillB
Interesting point. The Ensoniq MR76 uses ROM for permanent, FLASH for long-term storage, and DRAM for 'per-session' editing. Losing the FLASH functionality would be pretty serious, so I hope you are not right! :headbang:

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 12:05 pm
by where_theres_a_will_theres_a_way
Instruments with ROM, especially with ROM boot loaders, would be ok - because they can use the boot loader to re-program the FLASH. Devices that just have FLASH have a serious problem if they don't re-program themselves.

The cure, of course, is for the device to re-program itself every, say, 10 years. But then you have a separate set of problems like how does it know 10 years have gone by... requires battery, and a clock, and for someone to change the battery, and to put the right time in... can you guarantee the user will leave the power on whilst it erases it's own memory...

It isn't that the FLASH can't be used, it's that it is slowly erasing itself over about 20 years. At any point you can erase it and re-program it.... if the manufacturer allowed for it / kept the code / reprogramming tools and so on.

A proper can of worms!

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 12:15 pm
by BillB
Aah, that is probably OK then as regards the MR76. It does boot from ROM and the entire FLASH can be overwritten (with settings, patches, sequences etc). I thought you meant that it would lose the ability to retain new info. Slowly erasing old data is not an issue in this instance.

Thanks for the alert though. :thumbup:

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 12:27 pm
by Folderol
The worst of the lot are EPROMs. Good luck trying to find an EPROM programmer and the firmware these days.

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 12:34 pm
by BillB
Just bought an OS Update (last OS for the MR keyboard) on eBay. There seems to be quite a cottage industry in OS updates on EPROM for a wide range of devices, which presumably solves that problem? Or am I missing a technical point?

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 1:02 pm
by where_theres_a_will_theres_a_way
Well, it depends what sort of Eprom it is...

Originally the term EPROM meant Erasable Programmable Read Only Memory and the method for erasing it was UV light. So they had quartz "windows" which you covered up with a sticker (often with the software version printed on) so the light didn't get in to erase it. Once you wanted to re-program them you took the sticker off, shoved it in a UV light box for 20 minutes and presto-it was ready for programming again.

HOWEVER: They still had the same problem in that they forget eventually.. 20 years

EEPROMs are Eletrically Erasable Programmable Read Only Memories which tend to have longer retention - 100 years is common nowadays. However, EEPROMS are notoriously slow to access so they are only really used for user parameters rather than the actual programs. They are also relatively small in storage capacity.

Nowadays you can't get EPROMS that are UV erasable. The quartz windows were a real pain for the manufacturers so they are now provided "one time programmable" - meaning once programmed they will last for ....... 20 years.

If you let me know the part number (printed on the device) I can let you know how long it's likely to last.....

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 1:15 pm
by BillB
Oh the irony... it's got a big bloomin sticker all over it with the OS Update number.

Well, thanks for clarifying the difference between an EPROM and EEPROM. I previously thought it was just that one of them was from Yorkshire.

Presumably the good news in all this is that, as there is a cottage industry in EPROM updates, the OS data is obviously stored in (various private persons') computer systems for burning into EPROM, so the collective data is not in danger of being lost, just concentrated into a few hands. Not great, but better than nowt!

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 1:28 pm
by where_theres_a_will_theres_a_way
Yorkshiremen and E

Guy's wife dies. After the funeral he goes to the stonemason's to get her a head stone, chooses his preference and the stonemason asks what he wants inscribing. After a moment he says

"She were thine"

She was after all an avid churchgoer.

Two weeks later he goes back to see the wife and the headstone is there, it says

"She were thin"

The guy, distraught, goes back to the stonemason to complain. "You missed the E off" The poor stonemason is so embarrassed, says he will go back today and put it right.

The following week he goes back to see the wife. It now reads

"E She were thin"

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 1:36 pm
by BillB
where_theres_a_will_theres_a_way wrote:"E She were thin"

:bouncy: :bouncy: :bouncy:

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 1:53 pm
by N i g e l
I think the Moog Source used more reliable military grade memory but they probably weren't thinking of a 50 year lifespan !

Image

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 2:06 pm
by where_theres_a_will_theres_a_way
There you go Nigel

That chip at the front, it's an EPROM - has a quartz window and is erased by UV light or.... 20 years

The one behind it is the processor which is hard-wired so doesn't have the problem, though it does because the memories are all "evapourable" :beamup:

Re: Just 20 Years

PostPosted: Fri Aug 07, 2020 11:37 pm
by Eddy Deegan
N i g e l wrote:I think the Moog Source used more reliable military grade memory

It may well be decent memory but 'Military Grade' is a term much misunderstood. It doesn't mean "better"... far from it. It means "the cheapest that'll meet the basic requirements".

Re: Just 20 Years

PostPosted: Sat Aug 08, 2020 8:12 am
by blinddrew
And wrapped in a steel box strong enough to be squaddie-proof!

Re: Just 20 Years

PostPosted: Sat Aug 08, 2020 10:36 am
by Folderol
blinddrew wrote:And wrapped in a steel box strong enough to be squaddie-proof!
Impossible! :lol: