Above is the AmigaOS4.1 Final Edition running on the Sam 460CR, showing the MorphOS partition and Data partitions used by MorphOS. (Click to expand any pictures)
Below is the MorphOS 3.8 running on the Sam 460CR off the partitions shown above (MorphOS can't see the AmigaOS 4.1 SFS2 partitions):
The secret to getting this working was a tip off on the Amiga forums by Kyle (here) on how to boot from SDCard on the Sam460CR, in combination with the latest Sam 460CR/EX 2015-A firmware from ACube (shown in this blog here), which removes the 2GB restriction on SD Cards...It means I can install MorphOS 3.8 onto a large SDCard!
To get this working I opened the Sam 460CR case and installed a 64GB SDXC Card (stock standard - brand new):
The SDCard slot on the Sam 460 is mounted on the back of the board itself - here is the SDCard installed and ready to start work on it:
I first booted into AmigaOS 4.1 Final Edition and prepared an additional SFS0 partition called Data on the SATA hard disk (size 101GB) to be used by MorphOS. It can then also be read by AmigaOS4.1 and so sharing data is easier (MorphOS can't read the SFS2 partitions created by AmigaOS 4.1)
I then format the partition:
Note: I tried using SFS0 for the partition rather than FFS LNFS - it doesn't boot. So I stick with FFS LNFS.
The reason to do this ahead of the MorphOS installation, is to avoid drive partitions and names being created (like System: and Work: that MorphOS uses on automatic install) that conflict with the AmigaOS 4.1 partitions already in place on the hard disk (In AmigaOS 4.1 it already has two partitions called System: and Work:).
Here is the prepped SDCard in HDConfig, ready to save:
I can then remove the MorphOS CD and reboot the Sam.
To boot AmigaOS 4.1 Final Edition I just let the system boot as normal - it will then boot the hard disk.
As a test I then removed the hard disk, so that only the sd card remained. It won't boot at all without the hard disk, as the hard disk has the SLB_v2 needed for the Sam to run.
I guess you could install the SLB onto the SDCard if you didn't want to use a hard disk at all - haven't tried it yet though, and not really a priority for me.
Anyway - goal achieved! I can now dual boot MorphOS 3.8 and AmigaOS 4.1 final Edition on the Sam 460CR. No more opening the case to swap cables around! Fantastic!
I guess the next target is to triple boot Linux on the system using the former MorphOS SATA hard disk - another task for another day!