ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hello, I'm afraid my Beolink 7000 may have come to it's end with it's recent display problems. She's a USA MK II Type 1633 with 3.1 SW. Recently in "Stand-By" mode the LED display shows all exclamation marks except near the end where it has a forward slash & then one more exclamation mark. When the unit is activated the whole row becomes exclamation marks. If I manually turn off the remote with the stand-by key it will display "SUAOE-CY!!!!!!--". The LCD display shows all functions/changes/formats as normal. I am currently unable to test it further since my MX5000 after 21 years will not come out of stand-by. (The MX5000 went foul many months ago before the remote started it's "exclamation" problem) IR is still being emitted as seen my my IR viewer. I don't suspect the charger as I have checked it with both the table & floor models I own. I also have removed the battery pack for 24 hours to see if that could alleviate the display problem. (It did not improve) The lithium battery checks out at 3.28 volts although I have not released it from the PCB as I do not know what effects it would have on the software. Any thoughts or suggestions would be greatly appreciated before I start buying more 7K's for parts. It's in pristine condition so my quest is relentless. I apologize that the photos are not that great. Best Regards! Cary
I forgot to add that I have been unsuccessful in putting my Beolink 7000 into test mode via a 10 HZ signal on the data terminal. It may be because I'm just using a test disc with a 10 HZ tone and not a generator...
CK: I forgot to add that I have been unsuccessful in putting my Beolink 7000 into test mode via a 10 HZ signal on the data terminal. It may be because I'm just using a test disc with a 10 HZ tone and not a generator...
Could be, but there's really not much to gain with the test mode anyway. All it could do would be to tell you about an error, after which the service manual would tell you to order a new module this-and-that, which is not available. There are no detailed schematics or anything, so there's really precious little anybody can do to help.
So, not much to lose, and I would disconnect the internal battery as well for a complete reset. If it doesn't help, I'm afraid it's time to start looking for a ragged but functioning spare and transplant the internals into the good exterior parts you have.
EDIT: That "SUAOE-CY!!!!!!--" is obviously the correct "STAND-BY --" display with a lot of incorrect characters. So the problem might be a misbehaving solder joint or something ruining the communications between the display controller and the processor - but due to lack of documentation, I don't think there's much hope for anybody to fix it.
--mika
Thanks for your input Mika. I will take the lithium battery out of the circuit as a last resort. I feel bad even taking another 7000 down to save mine as this remote is so beautiful! 15 years of delicate handling but I still loose out.
-CK
tournedos:"SUAOE-CY!!!!!!--"
Yes, looks like bit 0 of the display is stuck to "1"; If you find the data sheet of those displays (I can imagine that they are some DLR2416 or so) you can measure if any short-circuit to +5V on DB0.
P.S. If they ARE DLR2416 you can look under osram-os.com where I got my datasheets from, although some time ago.
That's great news hemenex. Your advice gives me a place to start. I'll keep you posted as to what I find. Best Regards!
My US MK II Beolink 7000 has (2) HP Branded HDSP2112 in it. (Possibly the Osram equivalent PDSP2112) These are still available on the open market. Now I need to find out if it's actually the display or something driving the display...(I think?)
I would try removing all sources of power as you suggested first, and give it a few hours. It might be worth entering test as this allows you to perform a hardware test on RAM /ROM as so...
sine wave is no good (although I like your thinking!) and I found it has to be pretty accurate frequency wise!
Not sure I would like to remove any of those displays so see if you can find a short first and then it will be a matter of locating the correct display, assuming it isn't a problem elsewhere :(
Olly
Good thinking hemenex!
I don't think the problem is in the displays, as there are several of them and they all seem to have the same problem. They are most probably in parallel on the same bus and something is keeping the D0 line up, or the controller won't pull it down.
I read the Osram data sheet and still can't say whether the displays have an internal pull-up in the data lines... if they have, the fault could be as easy as an open solder, and I would look for that at the IC pin that drives that data bus line. There may be hope after all
tournedos:Good thinking hemenex!
Mika, thanks for the flowers
I do think too that it ain't the displays; this solder thing I suspect too, or a port problem of the microcontroller.
But alas, there are no schematics.
And frankly speaking I never opened a BL7000 as I'm glad mine is working... But I'll have a chance soon as I will get a broken one that I can do some training with. And I was raised with doing reverse engineering just for curiousity
Those displays were from HP originally, then went from agilent to osram finally. At least for now.
Gunther
Hello Step1 & Mika,
I did remove all power sources including the lithium battery and let it sit overnight. That did not clear the display problem. I need to find the microprocessor although I am unsure of its location yet. I did find another interesting problem with the display. If you set the LED display intensity to "Low" it completely disappears! Oh well, this will be more fun than I imagined... Just a few pictures of the PCB that the display is on. On the second picture the HDSP2112's are on the other side where the ribbon connector is located. The three large chips on the right side (LCD Display Driver) of the photo are where the LCD display resides on the other side. Forgot to ask...Test mode 10HZ square wave?
I know it is a long shot, but is it worth contacting B&O to ask if they have a circuit diagram. They did not release these as all 7000s were repaired by module replacement but they will certainly exist.
Peter
Peter: I know it is a long shot, but is it worth contacting B&O to ask if they have a circuit diagram. They did not release these as all 7000s were repaired by module replacement but they will certainly exist.
Has Beoworld not got enough clout to ask for that? Would be nice to get a diagram though!
@OP yes 10Hz 5v sqaure. unlikely to pinpoint any stuck IO pins but it might produce something interesting. I made my generator from a 4093 schmitt nand logic ic I had lying around and a couple of resistors / capacitors. Nothing fancy!
Update, Here are the results from putting my terminal into test mode.
In test mode there is no LED display at all unless you activate the region setting either EU or US. Then it only displays “I & #” but no “H”. When removed from the test mode the display remains incorrect & will not display the LED’s when re-engaged in test mode until the region setting is selected again.
The LCD display tests good and the ROM/RAM test is also good.
When in test mode the number keypad/or display assigns some incorrect numbers to the LED display as shown here. Number 1 is shown correct as 1. Then 2=3, 3=3, 4=5, 5=5, 6=7, 7=7, 8=9, 9=9, 0=0. (First photo shows # 2 key activated)
I would like to look at the microprocessor at greater detail but I will hold off on unsoldering the shield until I can swap out the display board first. (Time to go to the Beolink 7000 Boneyard)
Also some good came from this problem. After further inspection of the lithium battery I found it starting to leak. Just a small amount at the "button seam" that has not spread onto any components yet. (Ordered replacement regardless of final outcome)
Thanks to all!
UPDATE:
I swapped out the microprocessor board only and that did repair the display problem on my Beolink 7000. (As Beoworld member “tournedos” suspected it would be, not the display board) I’m still going to try and pinpoint the problem although this is not my best expertise. Only ten IC’s on the board including the 3.1 SW chip & EPROM/RAM. The temporary donor Beolink microprocessor is an older MKI so I would like to keep the 3.1 SW. I’m not ready to risk switching the SW chip. Any other thoughts would be greatly appreciated!
My only thought is that of amazement - and impressed by your skill. These devices were assembled by a particular team due to their complexity and the fact that the components are all surface mounted. Well done!
That's some progress!
This is hard to follow without having the circuit boards in own hands, but you would need to reverse engineer a bit starting from the actual displays. Look at the data sheet for the data bus lines D0-D7 and see which cable they go to, and where they end at the CPU board. The fault could be at the connector itself.
Great pictures BTW, one could almost use them to look for bad solders! The processor is the 80C31 by Matra-Harris Semiconductors, but it is really hard to find out without schematics whether the displays are mapped into the address space or just bit banged via I/O ports. Anyway I suspect the fault is somewhere in between.
Is that a space left by a ripped off component I see above the processor, next to the 33R resistors in your first picture?
Mika that will just be trace that peeled off with the can, but well spotted. He will need to make sure there is an adequate repair here just to be safe...
tournedos: Is that a space left by a ripped off component I see above the processor, next to the 33R resistors in your first picture?
Those connectors really are delicate and I agree this will be a very good first place to look! Also is it possible one had slipped out slightly at an angle?
Also interesting that we have a display controller on this board!
Peter, I wish I had more skill as “Step1” noted that my “solder sucker” removed the one pad for the shield tie point. (As first noticed by Mika) I blame it on heat perhaps more than the vacuum pump although I do have the temperature pretty low.
Mika, I’ll start the data bus troubleshooting. I kind of ruled out the ribbon cables themselves as I only put the defective board in the donor Beolink and it still malfunctions. (So it failed using the ribbon cables from the working 7000) I then put the donor board in my original Beolink and it works properly. Therefore the ribbon cables check out OK but yes the defective board could have a bad ribbon connector.
Back to the bench I go!
Hi CK just had a 7000 open but not enough time to really start looking as it only needed new EL backlight / lithium battery but I am sure the big IC on the switch board is a 5450 this being an LED driver - serial in parrallel out if I remember correctly. Now there is a small connector strip that goes to the display board so this might just be used to drive the upper leds but it might be something else to investigate (or at least eliminate) off the list just in case....