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820-2915 gmux flashing problem
- Thread starter protocold
- Start date
Why do you try the board without L2406, what do you expect?
Did you flash the GMUX correctly?
Did you remove R8904/11 before?
Did you flash the GMUX correctly?
Did you remove R8904/11 before?
i read on the demux site, it said that:
"For those with repeated failed flashes. We have determined the cause to be noise on the TCK line. This can be fixed by adding a 100pF capacitor between TCK and ground(GND).
If the above fix still isn't working for you, you can temporarily remove L2406 before flashing. Make sure to solder it back on when you are done flashing."
I still couldnt flash the gmux yet, it wasnt properly detected.
No, I did not remove R8904/11
"For those with repeated failed flashes. We have determined the cause to be noise on the TCK line. This can be fixed by adding a 100pF capacitor between TCK and ground(GND).
If the above fix still isn't working for you, you can temporarily remove L2406 before flashing. Make sure to solder it back on when you are done flashing."
I still couldnt flash the gmux yet, it wasnt properly detected.
No, I did not remove R8904/11
R8904/11 are not involved in GMUX flashing anyway.
But if you start the board with both in place, then may need to repeat the flash process agian (more than sure).
Personally I prefer to remove R2415, instead of L2406; more easy to do with JBC microtwezer.
I never had noise issue on TCK line.
Be sure to select the correct GMUX device from the list.
But if you start the board with both in place, then may need to repeat the flash process agian (more than sure).
Personally I prefer to remove R2415, instead of L2406; more easy to do with JBC microtwezer.
I never had noise issue on TCK line.
Be sure to select the correct GMUX device from the list.
Removing R8904/11 (at least one), will disable GPU power supply; economy reason, less heat, nothing more.
Is not a mandatory step, for GMUX flashing; but yes, in case of BIOS mod.
R2415, OR L2406 must be removed in case GMUX is not detected by programmer.
If OK, Diamond software will show you two device options to choose from.
Is not a mandatory step, for GMUX flashing; but yes, in case of BIOS mod.
R2415, OR L2406 must be removed in case GMUX is not detected by programmer.
If OK, Diamond software will show you two device options to choose from.
I think my board is messed up somehow, no matter what I tried it won't detect the chip. I ended up desoldering the gmux and found out that the TDO line underneath the gmux is not connected to the jtag pad (other jtag pins are fine). Maybe somehow the via was burnt? Maybe I have messed it up when I solder the jtag pads?
any tips/tricks for soldering the gmux jtag?
any tips/tricks for soldering the gmux jtag?
Use tiny wire (0.02-0.03mm is good enough) to rebuild the trace.
Maybe need to replace GMUX; from donor board.
Maybe need to replace GMUX; from donor board.