XB1 Controller PCB Scans, Traces and Info - 1797 "Elite Series 2"

[RDC]

Same chip, just different manufactures, and even then I'd be surprised if the things didn't come from the same place.

Now the PCAL6416A is a little different animal, though it still has the same pinout and core register commands as the others. That PCAL one I wouldn't swear would work 100%, but the TCA and PCA versions are pretty much identical.

[RDC]

Did some digging into this I/O Expander thing, and probably got this half wonky from the start, as I have been using the TCA6416 in my schematics, but the chip has always been the L16A, aka the PCAL6416. I just tossed a straight PCA6416 into a 1797 here and it indeed acted all kinds of stupid with only one button working and most of the other ones stuck on. Installed a new PCAL6416 and it works fine.

The TCA6416 and PCA6416 are pretty much identical chips, same 8 Commands so either one of those things will work the same way, and no idea why they wouldn't unless that TCA chip of yours is in fact a TCAL6416 version. The PCAL/TCAL has 23 Command, and in the case of the 1797 it does not like the non L version in there. I'll have to see what a 1708 will do with a non L version, but I don't recall it using anything more than the base commands. Could be the non L version will work fine in the older version controllers, but the 1797 is using more of the features the chip has, so the non L version throws a fit in there.

So long story short, yes the PCA is a direct replacement for the TCA, but when you're talking the L version, it's for sure not the same deal. Apologies for any headache that info gave anyone doing U4 swaps.

[Worf]

OK, I'll try using the PCAL6416AHF128 in the next device.

It has been confirmed that the PCA6416AHF,128 without the 'L' does not work.

[Worf]

Hi, I have a controller here that works perfectly well with a cable. However, once the cable is unplugged, it doesn't work wirelessly. The battery is fine. I suspect there is an issue with the BQ chip and would like to check if voltages are present when the USB cable is plugged in. However, since the BQ chip is facing downwards on the bottom board, I can't probe it. Which test point do I need to make jumper wires from the top board to the bottom board?

[rickW86]

Hi, could someone tell me the values of the components I highlighted in red on this photo? Would be very much appreciated.
sincerely,
Rick.

[MZ]

RDC,

I don't suppose you've managed to create the schematics for the MCU board yet, have you?

I'm trying to trace an issue with the D+ and D- lines. I can trace them as far as FT1 and FT2, but no further than that.


Cheers

[RDC]

@ rickW86 - Left one is 100pF, right one is 7.5uF



@ MZ - It's on the list, but that 0201 stuff is so fiddly to measure and most of the board isn't silk screened, so that adds another level of fun to everything. The USB lines are buried on an internal layer. They pop back out right before the MCU.

FT1 = RED
FT2 = GREEN

[MZ]

Thank you

[RDC]

Welcome.