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Freewave
09-01-2003, 01:18 AM
I flashed this IRD the first time without problems then I connected it to the TV, the unit turned on but I got no video. So I thought maybe it needs a reset. I went ahead and soft-reset the receiver but it won't turn on after I reset it any more. I reconnected the JTAG to see if I can re-flash it. However, JKey gives me the error "error reading from the ird (dcu peek)" as soon as I launch it. It did detected the correct device ID (0x2D4C...) and device (Sti5500). I retraced everything thousands of times already but couldn't find anything wrong. I know the JTAG is OK since I've used the same one to flash 3 more IRDs after this one. I even hooked up a different JTAG, switched PC, used Jkey from version 1.3.3 all the way through 2.9.10 with the same result (error out as soon as Jkey is launched). This IRD is write protected and have +5V on the FP pad, boot from link mode, etc... I'm half way decent with electronic so did some measurements to make sure proper voltage, resistance at proper places. I even un-solderred some of the main components (diodes, capacitors, transistors, etc...) and tested them off the board but couldn't find any thing wrong. Any suggestions to fix this stubborn IRD or should I just trash it???
Thanks
lefty
09-01-2003, 01:29 AM
Question: Did you remove the BFR connection after doing the whole process?
skinerd
09-01-2003, 01:37 AM
You make a conflicting statement:
"This IRD is write protected and have +5V on the FP pad"
If it is write protected you best not put 5v to FP.
Write protect grounds FP.
Freewave
09-01-2003, 03:36 AM
lefty - Yes. I did remove the BFR after the process.

skinerd - Sorry. I didn't make it clear. I have +5V on FP when I try to re-program only. Other time it's connected to ground.

Like I said, I've done a bunch of these before before, just this one is giving me problems.
skinerd
09-01-2003, 03:54 AM
lefty - Yes. I did remove the BFR after the process.

skinerd - Sorry. I didn't make it clear. I have +5V on FP when I try to re-program only. Other time it's connected to ground.

Like I said, I've done a bunch of these before before, just this one is giving me problems.

There is a 10k pull up resistor right at the BFR pad, follow the trace back to the CPU pin 27 make sure pin 27 reads short to ground with BFR grounded.
Freewave
09-01-2003, 04:05 AM
skinerd - Yes. pin 27 is shorted to ground when BFR is grounded.
skinerd
09-01-2003, 06:15 AM
it sounds like it is not going in to link mode........
Freewave
09-01-2003, 03:31 PM
How do I put it in link mode? Is there something else I can try? I've shorten the cable to about 3" from the JTAG to the IRD pads and about 8" from the JTAG to the PC. Still no lucks.
skinerd
09-01-2003, 05:13 PM
You can't make it go to link. can only hope it does by grounding BFR.
getting a device ID means only that you have power to chip, and jkeys sees it. Make absolutely certain the your jtag is connected correctly.....

I am returning a 420 to someone that tried to mod it, then sent it to me, I can't get it into link either, get the same errors as you do.......but he had some damage to the BFR pad area, and I was not able to repair.