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Firstly, the DEBUG tells you whether or not the EPROM loading circuitry and Main CPU circuitry is up and running. The opening message is something like "Emulator II, Copyright 1984 E-Mu Systems. The main CPU and EPROM loading RAM is functioning correctly (obviously)."

Second, It allows you to run a full RAM test and run RAM diagnostics (pushing data into certain addresses, etc). If one of the RAM chips is bad then you can easily determine which one by running this test.

Third, it will do a variety of tests on the disk drives. It will test drive compatibility and some level of media compatibility.

One thing it will notably not do is test keys/buttons/etc... There's a floppy-based utility for that. I think it's available on emxp.net.

On Sat, Dec 31, 2011 at 11:24 AM, Adrien <ad9@...> wrote:

Hi ! i wish you to have your emu II to work again.

Please guys, I heard several times of this debug eprom, and I’m wondering what it is exactly : does it indicates which IC isn’t working ? if the power supply has a problem ? anything else ? I’m quite interested and I’d love to know more.

Something possible , causing your emu II to not work could be the electrolytic caps which needs not to dry ( but over the years it get’s dry and it has to be replaced. You didn’t use your emu II for two months, and in some guitar amps for example, it can produce some problems sometimes. The theorical length of life of these electrolytic caps are sometimes lower than 5 years. The emu II is almost 30 years old. Although it’s possible to see some vintage 60’ marshall still working with the original caps.. but most of the time, peoples reform these caps, and it’s a specific process, and it isn’t gonna make them brand new anyway.

Happy New year everyone !

Adrien

De : emulatorII-list@yahoogroups.com [mailto:emulatorII-list@yahoogroups.com] De la part de Ryan Supak
Envoyé : samedi 31 décembre 2011 18:07
À : emulatorII-list@yahoogroups.com
Objet : Re: [emulatorII-list] No sound, Control Panel unresponsive, Sudden reboots???

For testing RAM, I've also had very good luck with the Debug EPROM. You can download the ROM itself from this site, and if you get to the point where you need help getting the Debug to run, post back here. I'll help out in any way I can.

rs

On Sat, Dec 31, 2011 at 2:37 AM, Mike <mrjdevries@...> wrote:

I also would measure the voltages on the PS.

But I'd suspect faulty RAM.

It may be the ram that runs the operating system.

(I've seen the exact same fault.. EII loads disk then crashes, and it was a bad RAM IC)

It may not be the ram that is bad, but it could be a poor connection.

(ie, reseat ALL the ram)

The service manual mentions what IC's of RAM run the OS.

And you can swap that bank with the sample RAM freely. (bad sample ram will have a distorted sound but the EII will still work)

Personally, after measuring the PS, I'd just go ahead and gently lift each IC up a few mm then press down. Then if that doesn't work, get hold of the memory test disk (or if you have HxC, an image of it)

Mike

Sent from my Apple ][e

On 31/12/2011, at 12:46 PM, "trickstar303" <trickstar303@...> wrote:

Hi,

My EII was working fine until today, when I fired her EII up after a pause of 2 months. It'll boot the disk just fine and the LCD displays the name of the loaded program. But there is no sound at the outputs, the control panel is completely unresponsive when any buttons are pushed and it will start to reboot randomly.

I opened her up and tried to push all ICs and ribbon cables etc, but it didn't help.

Does anyone know what these symptoms could be?

George

Re: [emulatorII-list] No sound, Control Panel unresponsive, Sudden reboots???

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