Another photo added here.
One of my DM500, I think have a corrupted bootloader, as after I removed the power supply and plugged it back only the green light is on and there are no response to the remote and no picture on tv.
I tried flashing using dreamup and flashwizard but nothing happened. The ip address of the dm cannot be found and using the comm port (null cable) flashwizard is asking to turn on the DMbox. Hence, I think the bootloader is currupted.
I decided to open up the box and try jtagging but I found the motherboard has missing jtag pins (see attached photo). Anybody had this one before? Is there a way to jtag these clones?
Hope someone can help.
Last edited by raygbmw1; 10-06-09 at 06:23 PM. Reason: photo added
Look Here -> |
Another photo added here.
Last edited by raygbmw1; 10-06-09 at 06:26 PM. Reason: Photo added
thats interesting, i just checked mine and it should have been just above those two Chips and that serial ribbon ????
Tagg
hmmm don't worry a new is only about $150.00
Adobe
yeah but I was looking forward in jtagging it as this will be my 1st time to do it and experience it. Also, it will nice to find if this can be jatagged.
just buy yourself a relook 400S their cheap twin tuners better then a DM500 clone.
Tagg
do a search for asta la vista and you should find posts on jtagging a DM500 or maybe use search terms of gemini and 4.3.1
Good luck
Leroy
Thanks Leroy but all those are for mobo with Jtag pins.
I was able to find schematic diagrams of the DM500 and the Jtag pins is jumper J61 and that the jTag cables 1,3,7,9 and 11 are actually connected to pins 20,70, 288, 68, 28 of the IBM chip and ground. I found the all the pins except pin 20. Any Ideas? I'll persevere and see what I'll come up with.
Last edited by raygbmw1; 14-06-09 at 01:28 AM. Reason: Pics added
The clone maker would have routed the other pins out because of R600-R603 pullups but as output pin 20 needs no pullup they probably left it unrouted. In which case you'll be SOL. Even with precise drilling it's near impossible to get at unrouted BGA balls without wrecking the board, because of the power planes.
won't work without a connection to processor pin 20. I'd say you're stuck with a brick. The only way to save it is probably to desolder and replace the flash memory with a newly programmed chip, which of course requires SMD rework equipment not to mention a fair bit of time. Not economic. Those clones weren't meant to be recovered.
Clone buyers beware: make sure your receiver has JTAG connector pads onboard!
pedro99 (23-07-09)
Hello
As written above, it must desolder the flash memory
Then reprogram the flash memory with a universal programming
Here the specific adapter
Last edited by bemol; 23-07-09 at 05:32 AM.
Now there's dedication for you.
Kids, don't try this at home!
[
won't work without a connection to processor pin 20. I'd say you're stuck with a brick. The only way to save it is probably to desolder and replace the flash memory with a newly programmed chip, which of course requires SMD rework equipment not to mention a fair bit of time. Not economic. Those clones weren't meant to be recovered.
Clone buyers beware: make sure your receiver has JTAG connector pads onboard![/QUOTE]
Hi
The track is destroyed or no connectiion
pin 1 on jtag plot four on the picture
CPU DM500 ____________________________________________ CPU DM7000
part of plots on dm500 CPU
best regards
Hello
I saw your photos raygbmw1 and this is the location of CPU with the title
Second CPU DM500 10 and Second CPU DM500 20. (the last two photos)
Remove the varnish by scraping gently with a cutter
to reach the plot Copper.
You can solder a wire, and you will again have a connection for the jtag (plot 1 )
First CPU DM500 10
First CPU DM500 20
Second CPU DM500 10
Second CPU DM500 20
and now the realization (First CPU DM500)
The same thing but with an enlarged view
Best regards
Last edited by bemol; 25-07-09 at 12:09 AM.
Those are some of the tricks that we used to do in the old days to overclock Intel processors! Ah, the nostalgia.
bemol's advice about pin 20 is correct and hacking that way is possible. But practically, with the soldering skills, tools and eyesight of most people, it's usually a bin job. I can't do half of what I used to do twenty years ago with my eyesight nowadays.
This is great! Thank you very much bemol. I like this very much. I will hijack my daughter's microscope and see what I can do. If I ruin the board then so what its heading to the bin anyway. If I manage to resurrect it the hey Great!
Thanks again. Will let you know with my progress.
Ray
great dedication raybmw1 ( only way to learn )
What a weekend and a day!
I managed to resurrect a corrupted dm500s mobo that has no jtag pins. I gathered all info about the jtag pins and was left with only one pin missing - pin 1 of the jtag.
This turned out to be directly connected to the IBM CPU pin No. 20. Thanks to bemol he pointed out the location of the pin. I followed his post above.
My first attempt was wrong. I painstakingly scrape the varnish on the side of the CPU using my daughter's microscope and a scalpel and then manage to solder a wire onto it.
It looked perfect but when I fire up the bootloader it won't connect. I reviewed what I did and found that I worked on the wrong pin. See the first photo. I suggest to use a 100x to 200x magnification for this exercise if people will be doing it themselves.
SO I had to do the same thing again on the other side where Pin20 is located - third photo shows where my first attemp and the correct location.
But this time my hands are abit tired and a bit more shaky. I manage to completely cut half of the copper as I scrape the varnish. I had to scrape more this time very close to the CPU black plastic top.
Because the round copper pin is now gone (as I said above due to my tired hands and finger) I can not weld the wire from the ribbon. I had to strip a piece of wire ribbon and tired to weld a strand in the exposed copper. You have to understand that this wire is just a little bigger than your average hair. It took me at least 4 hours of trying.
What I did was to put a bit of lead on the tip of the strand then stick this strand to place using the masking tape you see on the photos. I used the microscope to place it just on top of the exposed copper. Once in position I place the hot iron gently over the stand careful not to put it out of position.
I checked the solder to see if the strand is welded to the copper bit of the CPU. I lost count of how many times I repeated this but I manage to have the strand and Pin 20 welded together.
If people will try this use the strands in the ribbon wire as this is flexible. If you can get a flexible copper wire I think it will be better. The one in the ribbon wire looks like its not very good for fine soldering job. I had tough job trying to get the lead to stick to it. But thats what I had with me at the time.
Once I got this soldered I connected some piece of wires to the ends of the resistor R600 to R603. Note that the resitor side should be those closest to the back of the unit. I tried it on the opposite side and the bootloader does not come to life.
This time I connected the Jtag I made myself and fired up the bootloader. I had many goes before I manage to have a connection. I read somewhere that there is some timing issue with the bootloader and the powering up of the motherboard. Again lost count of the runing the bootloader and powering the dm500 but in the end it connected and now I have a working DM500. Yes.... what a feeling of accomplishment. All in all I used up my weekend but its worth it.
Thanks to bemol and those who help me in this endeavor.
Last edited by raygbmw1; 30-07-09 at 12:24 AM. Reason: Better pics added
best4less (06-12-11),nfnovice (30-07-09),urban_s0ulja (30-07-09)
bloody good work ray
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