Cue missing

[lightbyfire]

So here is an interesting dilema. I am running a Congo V4.3.0 and we believe we had a power surge two nights ago which caused a cue to loose all of its data. the cue itself is still there but no levels are recorded (including levels that are supposedly tracked through the whole show ie stand lights) which seemed odd to begin with, but now two days later the same thing has happend except only some channels are missing and there was no power surge, and in the meantime we have reverted to a saved copy. the board is also on a surge protector and UPS. im pretty much boggled by this one. any help would be appreciated

[JD]

Something is corrupting a data block. Just like your desktop, computer based systems will store the show in non-volatile memory (Eprom, disk, memory card) and load it into ram while actually running the show. Did the cue disappear while the console was off? or during the show? Systems are allowed to mess up once, but when they do the same mess up a second time something is wrong. ROM based integrated systems often use an error protocol that sets a data block to all zeros if it is corrupted. (This way the whole system does not stop on a bad read.) Any given cue may use multiple blocks. If the cue was lost during the show, it points to bad ram or a hardware failure. If it was lost between shows then it points to a bad memory card / drive / stick. If your unit uses built in Eproms for storage, a power surge may have damaged the Eprom or the write circuit for the Eprom. These are actually more vulnerable because Eproms often use a higher voltage (around 30v) for the write operation. Back up your data in a hop-scotch manner so you don't overwrite a good backup with a bad one. If it happens a third time, you should take the board out of the show and send it in for service.

[lightbyfire]

JD,

Thanks a lot, I can't say i really understand all of that, but it at least gives me an idea of the potential gravity. The ME has been informed and if we have another issue we are going to get a replacement. we had a monday show yesterday that went fine so i am hoping this has been some sort of series of flukes. (we actually had one more issue after i wrote the original message).

the only other thing that was strange was that when i wrote in originally it was intermission of the second show on a two show day. and the first show had no issues. the board was not turned off between shows. i dont know if the vulnerability occurs each time a cue list is started over or not, it just seems strange. however when i searched ahead at intermission for other cues without recorded channels it was clear but we did find a cue in the second act that had been corrupted. so this is something that seems to be occuring durring a show.

hopefuly we wont have more issues, and even if we dont well be sending the board in when we close later this month.

thanks again for your help.

[JD]

Originally Posted by lightbyfire

the board is also on a surge protector and UPS.

Just thinking this over. Since the show lost the cue without a save or shutdown involved, it may have been lost in RAM. There is one area that may be providing a source of noise getting into the board that may be causing this problem. The DMX output line. Although considered an output, noise can still enter here on the circuit ground path (pin 1) which, of course, should not be tied to the case of either the board or the dimmer. Still, all metal wiring acts as an antenna. Any spike on this line will be carried to the motherboard of the controller where it may affect other circuitry. I see cases all the time in the IT world where spikes to a peripheral component causes a system crash. You may want to try an opto-isolator inline on the output.

[lightbyfire]

Not sure if it matters but its running over ethernet to ETCnet.

[JD]

Originally Posted by lightbyfire

Not sure if it matters but its running over ethernet to ETCnet.

Ethernet has built in isolation at both ends, so it is unlikely to be the source of the problem. Sounds like its back to the board as the source of the problem.