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| I ordered 5 of those chips off eBay, my plan is to hot swap the chip and use that for BIOS foolery and keep the current one as a known good. | | I ordered 5 of those chips off eBay, my plan is to hot swap the chip and use that for BIOS foolery and keep the current one as a known good. |
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| == Ethernet desoldering == | | ==Future ideas== |
| I attempted to desolder the RTL8139DL chip I had broken earlier. Even with a large amount of flux and 40 minutes of hot air rework at various it didn't come off, instead making a flux mess and possibly damaging the board. | | Here's some things I'll try: |
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| I tried again the next day, changing my technique to use a larger nozzle, putting the nozzle closer to the chip and using tweezers to push the chip upwards to try and defeat surface tension. It worked!
| | *Check TFT panel signals |
| | | *BIOS flash |
| I prepared to re-solder the 6 lost pads, belonging to the following pins:
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| * GND | |
| * AD21
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| * AD20
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| * AD17
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| * IRDYB
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| * TRDYB
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| Only to find out only AD17, TRDYB were visibly connected. It's unclear where IRDYB connects, if at all.
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| == BIOS flashing ==
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| One night I was bored so I installed Debian 12 in QEMU then transferred it to the board's CompactFlash. The remaining Ethernet connector didn't work but I'm not sure if it ever connected.
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| I had some trouble with the RAM detecting. The board wouldn't beep due to lack of RAM but it also wouldn't initialize. Under a microscope the joints look bad, but I'm a little more suspicious of the SODIMM connection pins in the socket itself. The RAM doesn't feel like it snaps it properly, or maybe it's not making proper contact.
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| Only one Ethernet port shows, but even that one doesn't work. Maybe I've fried that chip? Though it wouldn't really enumerate. There was a resistor I lost when desoldering, that might be important.
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| The Molex USB to power connector also seems to have failed, because the crimping on it failed its once job of handling physical strain. I decided to just solder the crimp and be gentle with it for now.
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| Once Debian was up and running I used flashrom and chip hot swapping to try BIOS versions v1.18, v1.17, v1.16 and v1.15. None of them had any changes.
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| I gave up after a while until I decided to try the TV connector jumper on the board. I had tried this previously and had mixed results as it just seems to stop the boot altogether. When I tried booting it the machine didn't power at all. Removing the jumper also kept the system not booting.
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| I tried swapping RAM sticks but overall it seems like the slot really is failing in some way. But when it did work something interesting happened: The screen completely worked. I managed to see the BIOS screens and GRUB.
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| I'm tempted to believe this whole thing is some kind of memory issue, but that doesn't make much sense given OSes seemed to run just fine.
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| == Ethernet pins ==
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| While working on video 3 I was seriously, seriously confused about why IRDYB and TRDYB wouldn't be connected. It mades no sense, this is REQUIRED for bus transfer. The mystery is that I was looking at the chip upside down.
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| The real broken pins are:
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| * CLKRUNB
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| * REQB2
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| * GNTB2
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| * AVDD
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| * RTT3
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| * LWAKE | |
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| Most of these are test pins. The only ones that were connected was AVDD and RTT3, both should be fine left disconnected!
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| == Ethernet testing ==
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| I decided to try and figure out if the reason the remaining Ethernet was broken was due to me using the wrong type of Ethernet cable: I usually run small cross-over cables from the switch on my desk but the board may need an actual cable.
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| I booted the board and confirmed VGA works, but I was having serious problems with serial garbage. I had to send a break to get the Linux prompt to show itself.
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| Surprisingly, the board no longer acknowledges it has any Ethernet ports. It doesn't seem to show up in lspci either. Really not sure what is happening here.
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| I tried to reboot the board and go in to setup to check that. The delete key didn't work. In fact only some keys on my PS/2 keyboard worked. Same with a USB to PS/2 adapter. I did try to
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| VGA turned garbled very fast while the machine was running. I lifted the board up and found the RAM stick fell out. That's not normal, right? RAM sticks aren't supposed to do that.
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| Also the reset button isn't working. I think this started when working on the VGA port, not the BIOS or Ethernet.
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| I think the next step is clear: Fix the RAM slot.
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| == To-do ==
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| I need to:
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| * Repair traces
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| * Reinstall Ethernet
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| * Validate the USB power cable
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| * Fix the RAM
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| * Run a memory test using memtest86+ and its serial mode
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| * Debug why remaining Ethernet is broken
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| * Debug why PS/2 is broken
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| * Check if it was the BIOS breaking the VGA
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| *Repair the reset button
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