Emulator II - memory error

[dvdborn]

A "craaak" in the sound, or an erratic behaviour.

Explanation : Some of the sound memory is used as "scratchpad" memory, for the system.

The memory is arranged, if I remember well, in a block of 8x8 chips (unless you dont have the piggyback additional memory board).

First : take away ALL the memory chips by remembering their location and intervert them.
Is there a change ?

If the machine boots okay now, just sample music at maximum length (all the memory).

Listen to it. Is there a "crakkk" sound somewhere ? How long does it take to come ?

Now, intervert one quarter of the memories to another quarter

Sample again.

The cracckkkk sound has changed, in terme of the moment it occurs ? No ?
This means that the two quarters you have sawpped around are good chips.

Now, locate another quarter of the one of the two you didn't move and
swap the two halves of them. Location of the crackk has changed ? Yes ? You
are close to it. Now, swap the half of the quarter in two halves. Etc...

At last, you will find the faulty chip. In the WORSE case, it will take six operations to find a faulty chip out of 64 chips and 16 operations to find a faulty chip out of for 65536.

Now, finding a chip somewhere is gonna be something else...

Thanks to Dr.C dr.c@keyboardsrecording.fr for providing this info.

[Prometheus]

Is this "craaak" a long or a short one? I get more of a distorted sweep maybe ever third or fourth time i hit a key. Sometimes the key will get the sound from the key before, and sometime in unision, like a chord, and then the distorted "craak/craswooshrrrrchchrchcr". I got the rev0 piggyback. Any suggestions?

[Elmbeatz]

Is this "craaak" a long or a short one? I get more of a distorted sweep maybe ever third or fourth time i hit a key. Sometimes the key will get the sound from the key before, and sometime in unision, like a chord, and then the distorted "craak/craswooshrrrrchchrchcr". I got the rev0 piggyback. Any suggestions?

I bet that you have a voice problem (I've had that, too). The eight output channel strips are located on the 'analog' board, which is the left main board. I would reseat the chips on that board. That workd for me.