Loader?

[krupkaj]

How does the core loader works? If I understand it right I need to connect 4 wires between the tang nad the pico. Then copy the cores to USB stick. And what next? How can I open the menu for loading another core? And what about the ROMs for other systems?

[vossstef]

@krupkaj we need more documentation.... OSD loader open using : shift F12

unfortunately there are more implications that we need to document due to unwanted BL616 side effetcs...

It's mandatory to install the FPGA companion on the BL616 (too) !!!
The companion there (even if we don't use it and finally PiPico is doing the work ) is essential to avoid blocking of the JTAG interface that we need for the PiPico. BL616 companion is configuring the JTAG pins to input mode. If moon and sun are in full elipse there might be a chance that BL616 isn't blocking but you better don't rely on that.

In addition to that it's mandatory to power the Nano20k via USB-C Power Adapter and it must not be powered by a PC USB port. BL616 companion only need to be programmed once (dummy if you like just to ensure that the JTAG pins are ensured to be not driven, never to be updated again)

In case this this is not followed BL616 enters programming mode and the JTAG output pins are driving and PiPico JTAG pins as well (they are interconnected) causing OSD core download to fail.

A more robust and safe way would be to entirely disable the onboard BL616 by connecting BL616_EN to GND. Due to component size almost impossible for normal user (you need SMD rework place for that)