slavo...@gmail.com schrieb am Freitag, 30. Dezember 2022 um 00:41:26 UTC+1:
> Before you dive into that, it may be worth checking if the oscillators
> are stable and outputting what they are supposed to.

Just pulled out the 'scope, looking fine though.

I was having a good day, and swapped Miami. I've never replaced a 240-pin SMD component before, but that's kind of the secret goal of the project: discovering tools, getting hands on digital logic, leaving my comfort zone and becoming a better engineer.

Used a brutal, large heat gun to get the new Miami off the SSA adapter, carefully heating the zone bit by bit until it fell off, together with a lot of passive components. No serious pin bending there, and they all look pretty clean. Off to a good start.

Then I rubbed the Ultimedia's Miami pins with Chip Quik flux, and used an iron to attach a proper amount of Chip Quik low-temp solder to the pins. With an SMD hot air station I - more carefully this time - heated up the area until I could pick up Miami from the board with a pair of tweezers.
Cleaned up the board with even more flux, solder braid and iron.
Then cleaned everything with isopropanol and cotton swabs.

Applied flux again, and dipped the new Miami into place. Carefully wiggled it until pins were sitting perfectly aligned to the pads. Used a cheap USB microscope to inspect.
Then I used a flat iron tip and leaded solder to fixate some of each side's pins to keep Miami in place. Then went around the chip, applying solder to all rows, following with braid to suck up the leftovers.
Inspection - cleaning - flux - solder - braid - inspection... you get it. Until no shorts were visible or measureable.

Going to the bottom side of the PCB, I measured all 0805 sized resistors, and found R202 went up from 4k7 to 6k73. Replaced it - fine.

Plugged in the card, held my breath, turned on the -42T and.... things remain unchanged -.-
No additional failure, but no improvement at all. Still no way of reading out local bus addresses through the MIOBUSGET ioctl, and no successful driver installation.

So Miami survived the transplantation, but it wasn't the problem's root cause either.

Now I will replace all off-the-shelf components piece by piece as I find them available for a fair price - can't get any worse than swapping Miami.
It's about the journey, right?

Christian Holzapfel wrote:
> It's about the journey, right?