C&T F8680 emulation - 186 with 26-bit addressing

[Torinde]

Interesting 186 variant with 26-bit addressing (64MB RAM): datasheets

26-bit address bus enables 64MB memory map and allows direct support of PCMCIA memory card
Bank switching and high memory access overcome the 1MB addressing limitation of the 8086 processor, and enable PCMCIA and EMS support.

Memory subsystem (page 20/24)

The memory manager maps CPU addresses to physical RAM in 32kB or 64kB segments.
Once mapped, segments can be bank-switched for implementation of EMS memory and a PCMCIA memory card interface.
The maximum local system memory that is directly managed is 4MB.

A total of 32MB memory can be addressed through the 26-bit address bus ADR25:0 (the 32MB indicated when ADR25=1 is addressable only as PCMCIA memory) (rev 1.1)

A total of 64MB memory can be addressed through the 26-bit address bus ADR25:0." (rev 2.0)

• local system memory that is directly managed (4MB) vs total addressable memory (32MB/64MB) vs PCMCIA memory - what does "local system memory that is directly managed" refer to? Some custom mode?
• rev1.1 (32MB) vs rev2.0 (64MB) difference in "total addressable memory" - does that mean that F8680A supports more memory than F8680 or just the text in the brackets was removed from the documentation?
• "32MB...only as PCMCIA memory" - does this mean as some kind of emulated HDD/FDD?
• EMS specification maximum (32MB) vs F8680A (64MB)? How are the 32MB-to-64MB utilized on F8680A?
• can it use ISA card(s) for expanded memory in addition, for a total of 64+32=96MB RAM?

Has a System Management feature "SuperState R".

Kind of related are the following CPUs that have unusual memory addressing capabilities:

• 24-bit addressing mode allowing for up to a 16Mbyte address space:
  • NEC V33 (186 supporting also the real mode features of 286) - extended addressing mode via BRKXA/RETXA instructions
  • VAutomation Turbo86/186 1,2 - another custom mode?
• 29-bit addressing mode, 32 registers, VMZ instructions: VM8600SP - 8086 supporting some 286/386 instructions
• 386+ CPUs with 24-bit and 26-bit addresses (memalias)

Related:

• C&T F8680 emulation 86Box/86Box#4922, C&T F8680 emulation dbalsom/martypc#139