Question Wii not booting when headphone sense from RVL-AMP connected

[ss23]

I've got an assembled Ashida that works *almost* perfectly, but one of the final issues to resolve is getting the speakers working. The headphones work fine, but the speakers don't, presumably because I haven't connected the headphone sense from the RVL-AMP to the Wii. Unfortunately, when I do this, the Wii doesn't seem to boot properly. In terms of observables, everything powers on including the screen, but the screen never gets a signal (it says blue for a second or so, then turns off). When I've got the headphone sense disconnected from the Wii (or disconnected from the RVL-AMP), everything boots just fine.

My first thought was that this is probably poor soldering on my part, but the behavior seems reproducible. I have tried leaving the wire disconnected from either end (e.g. soldered to RVL-AMP but disconnected from the Wii, and vice versa) and the issue only happens when there is a wire going from HS on the RVL-AMP to the Wii via. This seems to indicate to me that it's not as simple as a poor job soldering or a simple short in the parts I've checked. Originally I was trying with some of the thicker wires but I have switched over to magnet wire to see if that makes a difference (it does not).

For reference, I have attached an image of where I've soldered onto the Wii. It seems clear from the documentation, but I'd like to confirm that this definitely is the right place for it. I tried both of the vias (you can see them both tinned), just in case something was not right with that trace, but neither worked.

I haven't been able to do much in terms of debugging since it seems to be a boot or not booting situation, but I have verified that the headphone port sense works as expected - NC, and changes when I plug in a device. Whether there are headphones plugged in or not though, it doesn't boot.

I checked the voltages with a multimeter in case that revealed something, but I don't know what I'm looking for, so it didn't help. Strangely, it looks like if I probe the HS on the RVL-AMP, I get ~1.7v (going from memory, could be a little more or less) regardless of whether headphones are plugged in or not. I found this confusing because I would have expected the RVL-AMP to be purely sensing/measuring on that pad, so seeing it at 1.7v was unexpected. This seemed to be the case whether a headphone was plugged in or not. I don't have another RVL-AMP to see whether this is expected though.

I'm happy to do more investigation to get it fixed, but I'm not sure how to approach it. There doesn't seem to be a lot of documentation on the RVL-AMP to know if it is misbehaving, or the headphone sense vias on the Wii, which makes it hard to know what to do next.

 

[Gman]

It does seem to be the correct wii via. Can you share pics of the rvlamp wiring too? Nothing comes to mind.. it's not normal behavior. It looks like there is a short on your AVE pins next to the H V sync pins.

 

[ss23]

For the shorted pins on the AVE, I checked the Wikibrew page on the AV_Encoder (avoiding the full link due to my less than 10 posts limit wikibrew/wiki/Hardware/AV_Encoder) and it looks like they're both grounds, so it should be fine. It does boot properly without HS connected, so I imagine this isn't the issue, but if we run out of other things to try I can always clean them up.

I have attached an image of the RVL-AMP installed on the Ashida PCB. There's an overhead light so you can see a lot of residue, but I've cleaned up a bunch of it since taking this photo just in case and it doesn't seem to have helped.

Since you suggested a short on the HS pin, I checked for dead shorts between HS and every other pin on the RVL-AMP and none were shorted, other than HL when no headphones are inserted, as expected.
With the RVL-AMP seeming to hold HS at 1v8 shortly after boot, I wanted to check for shorts to 1v8 specifically. Measured at 7.6MΩ between HS and 1v8 on the RVL-AMP, so it doesn't seem like that is the issue (though I don't have another RVL-AMP and Ashida PCB to check more specifically).

I also wanted to re-confirm the previous behavior. If I had headphones connected, the HS pin seems to be floating (or at least, not dead shorted to anything) until around ~1 second after boot, at which point it reads ~1.78v on my multimeter. This seems to be consistent every boot, and the only thing I can think of is that the RVL-AMP is somehow pulling it up to 1v8, but I don't have documentation to know if that is expected. The idea of a short did seem like the most likely idea, but if it is a short, I'm not sure what it would be between. Are there other pins that are driven at 1v8 but only after the RVL-AMP becomes active? I haven't checked the resistances between each and every pin, just my multimeter in continuity mode.

 

[fdraghi]

Does HS even need to be wired at all? I didn't and my headphones work just fine... I plug them in, the audio switches to headphones... take them out and audio on speakers resume.

EDIT: actually nevermid, just remembered I used a U-AMP 2 and not an RVL-AMP lol

 

[ss23]

Since making the post I've learned about the GPIOs and how they work, so I've done some more investigation.

Connecting a 270ohm resistor inline with HS gets the Wii booting, but the speakers still don't work. I can't rule out the speakers just not working though, so it is possilbe this is working as intended. Without being able to see the current headphone sense status, no way to tell.
I've also tried connecting to one of the other GPIOs without a resistor and that boots as expected. Perhaps one of my GPIOs is just glitchy and I can use another? I've asked Aurelio to build me a version of Hiidra that works with some of the other DEBUG GPIOs to see whether I have any luck there.