äImmediate
ä+:
no memory reference
ä-:
limited operand magnitude
äDirect
ä+:
simple
ä-:
limited address space
äIndirect
ä+:
large address space
ä-:
multiple memory references
äRegister
ä+:
no memory reference
ä-:
limited address space
äDisplacement
ä+:
flexibility
ä-:
complexity