Hacking WIP [Trinket] [Rebug] [Others] SWITCHBOOT_UF2 / FUSEE_UF2 modchip software

[snam11]

i know it could be a timing issue, but why if i remove both straps and i put joy on the d0 i can easily get flash connection?
btw lemme do the readings.black probe on gnd and the other on each side of the pads? in normal state and when pressing reset button?

 

[mattytrog]

Yes. When button not pressed, should show 3v ish. When pressed, should drop to 0

 

[snam11]

so in idle state i get 3.2v on resistor pad, 0v on condenser pad.
once i press reset it drops to 0 on resistor, and still 0 on condenser

 

[snam11]

i've also checked the solder points on the switch, and are same as your old installer topic.
only difference with the trinket is the joy stripe on the mainboard side:
on trinket both joycon pins are jumpered, on rcxm86 just the first on the left (mine is like this).

 

[josete2k]

If you flash the new bootloader the pad on the left is the vol+ strap.

I flashed mine's with joycon strap only bootloader and I had to change the d0 to d3.

 

[snam11]

If you flash the new bootloader the pad on the left is the vol+ strap.

I flashed mine's with joycon strap only bootloader and I had to change the d0 to d3.

i did also on mine at the beginning (with inverted d0/d3 straps i cannot get usb flash connection)
could you try to install also the vol+ strap so we can try together to solve the issues with this chip?

is your joycon strap soldered bridging both pins on motherboard or you've soldered just the left pin?

thanx

 

[josete2k]

Sorry, I don't have the console yet so I can't solder the vol+ strap.

The two pins for the joycon strap are bridged on the motherboard as I remember (I tested them with a multimeter).

 

[snam11]

so i played around for like 1 hour and now i can say i've managed to get any time the flash drive connected, but only when is useless....

with the standard installation 1 strap
joy d0
as soon i'm on horizon i press twice reset and i connect usb,100% of the times flash is ok

standard installation and also vol strap
joy d0
vol+ d3
as soon i'm on horizon i press twice reset and i connect usb,100% of the times flash is ok
the volume issue is still present.

with matty wire diagram and with bot strap connected
joy d3
vol+ d0
no flash connections, 0% of success ratio
but no volume issues

@mattytrog what do you think could be more easy to fix? vol issues on inverted strap conf, or keep on trying with yours (but i don't see any more resistors to remove )?

 

[mattytrog]

so in idle state i get 3.2v on resistor pad, 0v on condenser pad.
once i press reset it drops to 0 on resistor, and still 0 on condenser

That is correct. The reset pin is correct voltage. It has to be timing. I use bare chips in this configuration with just two capacitors on the chip legs.

Try pulsing the reset switch multiple times to GND. If you have flashed a switchboot bootloader, it has to open.

So... Forgive my ignorance... I don't own a RCMX86 so I am doing it blind. Are we saying that D0 is actually the joycon now? I'm trying to keep it same as trinket. That first resistor is pointless and why people were getting issues with locking up. It is simply incorrect board design.

--------------------- MERGED ---------------------------

so i played around for like 1 hour and now i can say i've managed to get any time the flash drive connected, but only when is useless....

with the standard installation 1 strap
joy d0
as soon i'm on horizon i press twice reset and i connect usb,100% of the times flash is ok

standard installation and also vol strap
joy d0
vol+ d3
as soon i'm on horizon i press twice reset and i connect usb,100% of the times flash is ok
the volume issue is still present.

with matty wire diagram and with bot strap connected
joy d3
vol+ d0
no flash connections, 0% of success ratio
but no volume issues

@mattytrog what do you think could be more easy to fix? vol issues on inverted strap conf, or keep on trying with yours (but i don't see any more resistors to remove )?

We just need to sort the pins out. Tell you what... When you hold down reset, and touch an led between 3v and should be d3, it should light brightly. This needs investigation. But the board design is incorrect anyway. It's not hard for the designers to look at a datasheet and make a correct board.

Two capacitors. That's all the chip needs with a clean supply which we have. No need for pull up resistors and shunt resistors and other nonsense.

The volume issue? Do you mean when you press reset, the volume increases? It's meant to do that by design.

 

[snam11]

theoretically the installation wire diagram on the github page shows the joycon strap on d0 (the first pin on the lower left of your installation pic)

https://github.com/euclala/RCM-X86/tree/master/internalDongle

with this conf (and also with vol+ on d3), the flash connection is ok.

with your reference pic (straps are inverted), with BOTH straps connected,is impossible to have the flash connection.
BUT if just the vol+ on d0 is connected, flash connection is ok!

so i think is a problem related with both pin d0/d3 connected (vol issues on original conf, no flash connection on your conf)

i hope it helps to understand a bit more about it.
And no need to be sorry, i wish i had your skills to do 1/100 of what you've already done for the community...

 

[snam11]

That is correct. The reset pin is correct voltage. It has to be timing. I use bare chips in this configuration with just two capacitors on the chip legs.

The volume issue? Do you mean when you press reset, the volume increases? It's meant to do that by design.

in this config (joy-d0 vol-d3)the volume is unresponsive, it rises at max, like vol+ is always pressed.

 

[josete2k]

For flashing I do the following:

Connect USB to the computer
Start hHorizon (it autostarts when I plug the USB)
Power Off console
Double RESET
Done.

 

[mattytrog]

in this config (joy-d0 vol-d3)the volume is unresponsive, it rises at max, like vol+ is always pressed.

In all circumstances or just when you hold reset?

 

[snam11]

as soon the chip is powered on.
also on hekate i can see pressing vol- is like pressing vol+

 

[mattytrog]

as soon the chip is powered on.
also on hekate i can see pressing vol- is like pressing vol+

OK. Going to update things. Thank-you!

 

[mattytrog]

@snam11
Will you try these please?

Solder as picture...

Extract zip...
Choose both_pins.UF2, flash that
Flash test.uf2

Tell me if all is good before I publish? Will be in other modchip thread when I publish.

 

[snam11]

just tested and......
it WORKS!!!

i get flash connection also if usb cable is connected and i double press the reset button.
double tap it has to be little bit faster than usual but it works, so i don't care much

mate thanx a lot for the help and support

if u need to test something more just let me know (i'll keep the switch open for a little while)

thanx again

 

[Romain80200]

So, we have to remove the 2 resistors and use the new soldering diagram?
Thanks.

 

[snam11]

on mine i've removed both restistor, but i'm not quite sure is mandatory.
only @mattytrog can tell you for sure

 

[Romain80200]

ok, i will be ready to solder mine as soon as will get it.

 

[mattytrog]

Using this method, you don't need to remove any resistors. Doesn't matter if you have (that usb logic chip... What is that for??? An opamp? Protection? Just not necessary)

Remove them, don't remove them, doesn't matter

I think I get it now. What the creator of this chip has done I think, is attach the usb logic chip for sercom debugging I think. This is bound to cause problems with the trinket pinouts. But now we are using different pads, no removal is required.

Very strange design of board... Still, glad it's now working.