Counter with Index

This addressing mode requires one word of extension.
The operand is in a memory location referenced by an effective
address computed by adding together the contents of the program
counter, a second data or address register, and an 8-bit displacement.
The value in the second register can either be a full long word or a sign-
extended word value. This is specified by a .W or .L extension after
the register. If no extension is used, the assembler assumes a word

Mode:\b 111 \bRegister: 011

Assembler Syntax:
d8(PC, Rn)
d8(PC, Rn.W)
d8(PC, Rn.L)

\i11DA,3Register,1WL,---88-bit Displacement,

DA field: contains a 1 if Rn is an address register, 0 if
Rn is a data register
Register field: contains the register number of Rn
WL field: contains a 1 if the entire long word value
contained in Rn is to be used, 0 if a sign-extended
word value is to be used to calculate the effective
address of the operand.