Hi,
"a few" days ago I created a document:
S12XD, S12XE - External BUS design - Addendum To AN2708
Where you can find practical approach to solution. There is also SW available.
I also suggest you to read AN2708: https://www.nxp.com/docs/en/application-note/AN2708.pdf
Best regards,
Ladislav
PS some more examples can be found at: