On p.78 in the V850/SA1 Hardware Manual document number U12768EJ4V0UM00 (4th Edition), there is a description saying,
When connecting an external memory, can I use an in-circuit emulator to debug it?
Yes, you can.
This description only means that emulation of the MAM register is disabled.
The operation itself specified by MAM can be emulated.
The item to be set by the MAM register on the device must be set by a jumper (J1) in the IE-703017-MC-EM1.
For details, refer to 2.5 "Separate Bus Function Setting " (Table 2-5) on p.24 of the IE-703017-EM1 User's Manual.