E-mu Emulator Sampler User Forum for the EIII EII EI and EIII XP

General Category => EII Technical Issues / Tips => Topic started by: rediatek on August 09, 2009, 01:43:41 PM



Title: EMULATOR II TIP / Service Manual
Post by: rediatek on August 09, 2009, 01:43:41 PM
Hello

Found this on the internet, it may answer to some general questions of many.
http://www.emulatorarchive.com/assets/PDF/EII%20Diagnostics%20Manual.pdf

Could anyone please tell me where I could find EII service manual online?

Thanks a lot

Redi


Title: Re: EMULATOR II TIP / Service Manual
Post by: dr.c on August 09, 2009, 04:05:26 PM
Dear Redi,

Please, please, please, don't take this personally, its very nice to have sent this adress to get this document, its very gentle, but this document from E-Mu is a huge piece of shit, I have NEVER found a way to get the machines working by following the instructions.
The Memory test Eprom HAS BUGS, believe it or not ! Anyway, if there's a fault, memory test eprom or not, if the circuitry is bad, it will just NOT WORK !
The same for calibration : there is a calibration diskette but I have ENEVR used it just because the machine has to be completely calibrated before it hets hot, wich means a matter of four minutes. After this delay, the circuitry drifts and theres no way to calibrate anything ! 999% of the faults described on this document were bad power supply or unsufficient reset delay at power-up.

Thanks anyway, but all of you guys, forget about it. It can, by times, be as well the "scratchpad memory", wich means one or a few of the first memory sound chips wich are bad. Just swap, and try.


Title: Re: EMULATOR II TIP / Service Manual
Post by: Chaztech on August 20, 2009, 04:16:49 PM
Hears what i think i have figured out so far.
I think my tests bare this out.
First the Cpu loads Eprom data into its local ram to run basic functions and order boot load.
Then it reads from the drive and loads that into memory starting with IC13 to 20 for boot section and the rest of memory for sound and patch data etc.
the first part of the ram segment1 must be good for the boot load to complete. if any of the 8 chips has a fault in its first area of ram it will hang. if the area is good it will boot but may give distorted sound or other oddities due to more dead memory segments.
one quick way i tested each ram chip was swap into ic13 and watch for boot hang. with the memory test disk this is easy to do quickly as it will show a bad segment up right away.
I found many 8 chip bank areas had several bad segments in several chips so it can be hard to nail down witch chip is is dead!