Problems with a 1.6b Xbox

[satresar]

Hello, I'm having a problem using modxo on a 1.6b Xbox (The one with Hynix RAM chips). I have already rebuild the LPC but no matter what I try, it just boot up on the stock BIOS. This Xbox was using a Aladdin XT chip to boot up, so the LPC rebuild is techniclly good, exept that the LFRAME point in the board was conected to the Aladdin XT chip on the D0 point and BT and L1 points were conected to referd points. I tried to ground the LFRAME point but the Xbox just FRAG. Any idea in what is going on? I'm gonna leave some pictures here to see if anything is wrong.

In adition to this, I'm very new to the Rasberry PI Pico, so there is any way to see if the Pi Pico is working as intended? Like a serial monitor on the PC. I have been following the project since the launch and in the instructions it says that the LED on the PI Pico will blink if there is no BIOS file, is it still working that way? If so, shoud it be blinking while it conected to the PC? I'm sorry if this is a really long message but I'm very interested on doing a 128 MB RAM mod and modchip with Xblast its kinda required.

This is how the LPC rebuild looks like

And this is my build of the Modxo chip.

Btw, saludos desde Colombia, quisiera haber escrito todo en español pero me parece mejor si lo escribía en ingles y si de ser posible me puedas responder en ingles por si alguien tiene el mismo problema en el futuro y no sabe español.

[satresar]

So, I found what's causing to not boot into the BIOS I flash, and it's the Raspberry Pi Pico. Looks like, for whatever reason it doesn't work with ModXo. But the strange event happen here: I order some 16 MB flash RPIPICO knockoff on AliExpress and that Pico actually solve my problem. The presumably faulty Pi Pico works with some simple code like a blinking LED but with ModXo it just don't work. I just detect the strange behavior while putting the 0.0v .uf2 ModXo file, where it should be a blinking LED when there is no BIOS, but it didn't show up. What I'm assuming is that this feature was removed in the 0.1v because on the working one before putting the file it didn't show the blinking LED as previous version.

So, now I have a fully functional ModXo 16 MB RPIPICO, the same that in the previous version was reported to not working, just booting up my Xbox with a CERBIOS as a test. Just speculating, maybe this kind or errors happens when the Raspberry is bad or partially bad, some key component must be interrupting ModXo to work properly on those board, on the "branded" ones and/or the 16 MB knockoffs.

Could you please reintroduce the blinking LED (if it was removed) feature for future debugging like in this case scenario? Thanks again for your work, a pretty interesting project taking into account that some people some years ago suggest that the Pi Pico was to slow to be able to hack the system, how wrong they were.

Here some pictures of the new build:

And here the glorious CERBIOS logo booting:

[shalxmva]

Hi, i saw from people that there are some boards that didn't work even if those are the same as known working models. I am trying to improve the code to increase compatibility.

For the LED, it only flashes if there is only the modxo image flashed but no bios.

I am trying to add more error detections. By now, if the LED Flashes, there is an error message printed through the USB Serial Port.

Saludos desde México!!!!

[marcelo-jrkiko]

Hey Guys. From Brazil.

I believe I'm having the same problem on my Xbox 1.6. I tried for hours with a Pico and RP2040-Zero.. And nothing. I believe there are bads "ripoffs". I noticed that both are problematic to enter BOOT mode.

Anyway, I'm going to purchase other Picos and test them.

I believe it would be interesting to implement a debug mode that, when enabled, reports step by step what is happening via the USB Serial port. It would help a lot, I'm thinking about maybe implementing this, at least the initial part of the code.