The Yamaha AN1x Synthesizer mailing list

Jeff a \ufffdcrit :
> Jerome St-Pierre a \ufffdcrit :
>> Never mind. I searched some more and other users said we must make a 
>> backup
>> before changing the battery.
> YES, unless you don't mind to loose all the patches stored in your 
> keyboard (i.e : you have them on your computer as .an or .mid files...)
>> But I still have another stupid question. I don't understand how 
>> removing
>> the battery could affect the patches? Aren't they saved on some kind 
>> of hard
>> drive? Or are they really kept loaded in memory with the battery?
> YES. These patches are stored in a static CMOS RAM (not a flash 
> EEPROM...) which in "stand by mode" is supplied by the back up 
> battery. The extremely low, but not null, supply current (a few nA) in 
> this special mode allows years of storage without the help of the main 
> P.S. But without any supply all is wiped out . When the AN1x was 
> designed, flash EEPROMS vere too small and too slow, and a hard disk 
> would be too huge and too expensive to store only a few tens of 
> kbytes. An AN1x patch is not a sampled sound but only a few lines of 
> data and instructions.
>> I have no clue since I never did anything like that...
>>
>> Thanks for your help!
> If you don't want for some reason of your own to make a memory backup 
> on a computer you can try the "kamikaze way" : open your synth, turn 
> on the main supply and then change your battery BUT take care of short 
> circuits when you're doing that. The screwdrivers or pliers are 
> obviously conductive, but the battery itself (even flat out..) too : 
> don't touch anything else with any metal part. When the main supply is 
> "on" the RAM is in "active mode" and does not need any other supply.
> Cheers.
> J.F.