Kernel & SuperBASIC Updates
Kernel and/or SuperBASIC Releases
Official firmware releases that routinely improve SuperBASIC, MicroKernel and other built-in software, are published at https://github.com/wildbitscomputing/firmware.
If you want to apply a Kernel and/or SuperBASIC update independently, you could do so piecewise by replacing only the SuperBASIC or only the MicroKernel flash blocks, available from the corresponding Github repos:
USB Port
F256 Jr. / F256K
You will need to have the XR21B1411 USB Driver for PC/Linux. The MAC is outdated. (Note: Driver is not needed for the F256K2) [1]
F256K2
On the F256K2 the XR21B1411 has been replaced by a FT4232, to allow direct use as a JTAG controller for the FPGA. There are 3 virtual serial ports (channels) enabled. The first connected to the Raspberry PI Nano (on-board) that manages the FPGA loading, the second one is the Debug port, and the third one is the system UART. This means that you only use a data supporting USB-C cable running from a modern computer to the back of the K2, no need for a specialty cable, nor a specialty adapter.
Therefore, on a F256K2 you want to select the second COM port that gets added to your system. As an example, on one Windows 10 system, the F256K2 USB-C connection added ports COM5, COM6 and COM7. All three coming up just as generic FTDI manufacturer USB ports.
Update batch file to point at correct port
To perform a full Kernel & SuperBASIC update, I simply downloaded the Complete Package (above) and edited the update.bat batch file to instead specify my system's COM6 (i.e. the 2nd added Port).
Links to Software needed to do update with FoenixMgr (Python Script)
Python [2]
PySerial [3]
Foenix Manager (Collection of Python Scripts to use the USB Debug port) [4]
Kernel and/or SuperBASIC Update Guide
Below, is a short video on how to install the software you will need to be able to reflash your Kernel and/or SuperBASIC.
How to Update your F256 Jr. / F256K Short
How to Update your F256 Jr2 / F256K2 Video
Starting at 6:46, this video dives into updating the firmware for a specific core (each core have their pocket of 512K of flash memory, not shared).