DISCLAIMER: These notes are from the defunct k8 project which precedes SquirrelJME. The notes for SquirrelJME start on 2016/02/26! The k8 project was effectively a Java SE 8 operating system and as such all of the notes are in the context of that scope. That project is no longer my goal as SquirrelJME is the spiritual successor to it.
Was a busy real life day today.
Pledged for the CI40 on KickStarter so that I can eventually port this OS to said device, it will ship in April of 2016 however so that is many months from now. Hopefully by then I have an actual working system since by the time I have right now I am getting closer. Just need to write out binary file formats. The nice thing about it is that it is going to be very open which is a good thing. The device should prove easily hackable and simple to port to. I should eat right now, then attempt to continue outputting KBF files so I can eventually boot something.
The MikroBUS looks very interesting. They have shields and capes for the arduino along with the BeagleBone Black and Raspberry Pi (which I have). There is most likely no auto-detection stuff however so it might just be a manual tell it that it is being used kind of thing. However, due to the fact that the set of required GPIO pins and such are of a standard set (SPI, I2C, etc.) I can set up a driver interface which is a MikroBUS slot. Then a driver which supports various boards for it could just rely on a MikroBUS slot interface. The same could be done for PCI devices however the MikroBUS is much simpler despite the lack of potential detection of attached devices. So it is kind of like PCI or USB but just based on a port rather than negotiation and such. For the CI40 however I just got two base boards so I would need to purchase any extra click devices. With a microSD and a click board that offers memory I could write a MIPS emulator for the arduino. Alternatively one that can do microSD and store a bunch of memory in one card would then have the possibility to have extra expansion. There is even an ethernet click board.
There is even a PS/2 click board. So this stuff seems pretty versatile.
Personally I thought about having a fake PCI port made entirely of GPIO pins. A PCI click board would be interesting, but most likely insanely slow. There is also a RS232 click board which is nice. So having many easy to use prefabricated expansions is quite nice for board development as you no longer have to guess with chips and instead just prototype much faster.
A am a bit away from drivers right now however, but it does not hurt to dream at all.