Behringer DDX3216 - Trying to repair, please help!

[Steve Conner]

Well done! That was a serious desoldering job.

To remove a dead QFP, I prefer to cut all of the legs off using a Dremel with the cutoff wheel attachment. Then it's really easy to remove the severed legs from the PCB pads. Anyone reading this with proper SMT rework equipment, please don't hit me!

[Jazz P Bass]

Wow!
Nice job.
My worst encounter with flatpacks was a Panasonic preburned microcontroller.
40 x 100.
The first one that they sent me was blank.
That is correct, never burned.
There was a small initial marked on the box, on the ones that were burned.
The first one was a bare white box.
Panasonic was pretty cool about it, after I convinced them it was indeed blank.

[Roxtech]

DDX3216 PSU Schematics

Does ANYBODY still have schematics for this beast? I've tried downloading from the sites already published on this thread, but apparently the files are no longer available. I would really really appreciate it if somebody could either send me a copy or point me in the right direction where I could find them

Thanks in anticipation.

Andre.

[fast-rentner]

Does ANYBODY still have schematics for this beast? .

Take a look to

Download DDX3216.zip from Sendspace.com - send big files the easy way

good luck

[Roxtech]

Thanks to everybody who sent me schematics!

So now I got the power supply working... the desk lights up like a Christmas tree when I switch it on! The supply lines seem pretty stable on a 'scope, so I assume that a CPU is not switching on properly?
I have not seen a solution for the "many random lights on at power-up" problem on this thread (or maybe I missed it), but is there a quick & easy fix for this before I plunge into diagnostics again?

Cheers,
A

[fast-rentner]

Before you go on testing, you should check if all cabling is done in the correct connectors !!
I read of some guys, who made mistakes while replugging, and got additional faults due to higher voltages on wrong boards.

If you´ve cheched to be correct, take a look to the 31.x kHz crystal. This one is the main clock of the cpu. Somewere in the beginning of this thread, John stated, this is one of the major fault reasons in their database.
The CPU is responsable for the user interface, so there could be a fault.

I´v seen this behavior only once on my console, during a live show :-((
Power recycle solved the prob. This could be a hint to some trouble in the power supply, but I´m not shure.


Han told about a similar prob, and he changed the cpu, but there is not result yet.

Jens

... think, I have to speed up my translation engine

[Marcellino]

Hello,

I've also a problem with my DDX3216. I've determined that two of the 4 Flash (4MB) IC's are not working anymore. When changing from a working DDX3216 it's working again. My question is : who can provide for IC15, and IC18 a HEX file or equivalent for reprogramming a new am26F040 Flash memory?

Thanks in advance,
Marcellino

[Marcellino]

test

[soundmandoug]

Hi all, I also have a DDX3216 with what may be a familiar problem. When powered on, the display initially comes up with the splash screen, but after the 14 seconds or so, when the display changes to "channels 1 to 16" the two rows of squares appear, but no sliders underneath. Also, when the power is first applied, the faders don't move down, as they do on a working mixer (I have two units - one working, one with this fault).

I've removed the power supply, built a dummy load and checked it out. There was some noise on the +-8V supply (and it was squeaking), which I traced to the SMPS chip on that section. I've replaced the chip and the +-8V is now quiet.

However, when replacing the PSU, the fault is still there. I've checked the 32.768MHZ oscillator on the CPU board and it's oscillating fine (I replaced the crystal for good measure, as I had a spare one, but now effect).

So, I'm presuming the problem may be with the board with the PIC on it, but here's where I could use some advice. Anyone seen this before?

Thanks a lot

Doug

[Marcellino]

Hi Doug,

I think you should check the CPU board. The 4 Flash (4MB) IC's data content could be corrupt. That was the problem in my case.
Try to find a working unit and pull out a complete working set of 5 IC's in a row: (IC15-IC19) If your unit is working again you can use these "pulled" 5 IC's as source to copy the hex data with a simple flash programmer (Ebay, China, about $30) to re-program your IC's.

Good luck,

Best regards,
Marcellino

Hi all, I also have a DDX3216 with what may be a familiar problem. When powered on, the display initially comes up with the splash screen, but after the 14 seconds or so, when the display changes to "channels 1 to 16" the two rows of squares appear, but no sliders underneath. Also, when the power is first applied, the faders don't move down, as they do on a working mixer (I have two units - one working, one with this fault).

I've removed the power supply, built a dummy load and checked it out. There was some noise on the +-8V supply (and it was squeaking), which I traced to the SMPS chip on that section. I've replaced the chip and the +-8V is now quiet.

However, when replacing the PSU, the fault is still there. I've checked the 32.768MHZ oscillator on the CPU board and it's oscillating fine (I replaced the crystal for good measure, as I had a spare one, but now effect).

So, I'm presuming the problem may be with the board with the PIC on it, but here's where I could use some advice. Anyone seen this before?

Thanks a lot

Doug

[soundmandoug]

Thank you so much Marcellino, as you've shown me where to look. I tested the Vcc on the memory chips and at first thought that they were down at 1.6V, but I must have been misreading something because I've checked again later and they're up at 5V, so all seems well with their power supply. I'll see if I can remove the working ones and check - although I REALLY don't want to break my working mixer!!

Doug

[soundmandoug]

Latest - I swapped the upper sections of the mixers over and put the upper section of the non-working mixer onto the bottom section of the working one - and it worked! So, as Marcellino suggests, the fault certainly lies in the bottom section. Next I'll swap the CPU boards over, but just before I do, is there any risk to any of the working components when I put the non-working CPU board in (or put the working CPU board in the non-working mixer)?

Doug

[S2udio]

Hi just joined here and have lots of DDX3216 data to share and will in the near future be putting
up all the EPPROM files for the CPU board as well as the PIC chip files (the pic 16c554 gets its data from the epproms on power up and is not retained on chip)

Tip if you are recapping the PSU, replace all the electolytics ,yes all of them !
I use 130deg samwa's.
NOTE do not get the 7 pin CTRL11 and CPU01 connectors swapped,as a freind found out !!
As already stated the 32 meg xtal is a common failure,also replace the electros with tants,
On the cpu ,and all the smaller caps on the DSP,and the two 470uf with samwa.
These increase the stability in all the digital circuits !(behringer cost cutting)
I have almost compiled a fault test log showing what is displayed on the LCD with the various
sub boards connected, the analog IO boards do not have to be present for a good boot seq !
I am currently modding the analog boards with better op amps and caps.
I have a small supply of cpu chips (elan sc300) if your stuck with cpu death and
competant at replacing,or I can repair and test the cpu/dsp boards (for a fee) for you.
Be back soon

[soundmandoug]

Hi s2udio, thanks a lot for your reply. I'm also very new to this forum (just the last week) as I've just jumped into digital mixing after 30 years playing with analog. This is such a brilliant desk and well worth the patience fixing broken ones. I'm about to try swapping the memory chips between my working (nice new shiny, expensive!) and non-working (had a very hard life, missing a knob or two) one. I'm in fear of bending pins on the chips, as the sockets are VERY stiff and I no longer have tools such as IC removal clamps (I was an electronics engineer a very long time ago, but just dabble at home nowadays).

Thanks for the offer of info. If I find that it's a memory chip that's gone, how do I reprogram them? I have a couple of spares coming from Hong Kong (courtesy of ebay) but I haven't found a programmer for under a few hundred quid. I play with PICs a bit and have some serial pic programmers, but I guess I won't persuade them to work with the AMD chip, right?!

Doug

[S2udio]

Hi Doug
As you say these desks are one of behringers Good products,apart from the poor quality electros and chinese build quality,
Though the PCB's are of industrial quality ! I luv'em
I have a small quantity of spares as well,so if you're stuck let me know.
I have found the epproms to be very reliable ,and not found a dead one yet,(maybe lucky) !
Although a sickly psu with a overvolt 5v rail may cause failure.
A reseat of all the epproms first,a small sharp blade screwdriver gently applied under each corner and lifted will do it.
Whats the actual boot sequence before it fails ?
Ah sorry just read your post.............
Thats a new one ! strange i think the cpu boot prom checks for corrupt data ?
What happens if you try a factory reset ?
I see you have a working board as well,swap the eeproms one at a time !! or you
wont know which on is faulty.
ps try the cpuos boot first, IC19

Paul