In the address ranges $4000 0000 - $7FFF FFFF and $0000 0000 - $3FFF FFFF 'normal' 32-bits transputer read/write cycles are mapped onto D32 VME-cycles. 'Normal' is when address bit A28 is NOT set. If A28 is set a single D16 cycle will be performed (see section 3.5 on D16 cycles).