Originally Posted By Al Kossow
Originally Posted By Edstrom
Why is A24 an invalid address width? It has special meaning in VME. Should I add it?


The 68000 only supported 24 bits of address. 68012 (made for HP) had 25 bits. 68020 and beyond were 32 bits.


checking the spec

Option A24 specifies that all addresses generated by the MASTER or decoded by
the SLAVE will be restricted to no more than 23 bi ts. Option A32 selection
extends the address range to 31 bits. The address modifier lines indicate to
SLAVES whether the address is 15, 23, or 31 bits. Option A32 also requires an
expanded bus system.