The 65816 has valid data address (vda) and valid program address (vpa) pins which are essentially the same as fc0/1/2 , minus the supervisor/user mode support.

    vda  vpa
    0    0    internal operation, address bus may be invalid
    0    1    valid program address, may be used for program cache control
    1    0    valid data address, may be used for data cache control
    1    1    opcode fetch, may be for program cache control and single step control