Unpack binary coded decimal

NAME
	UNPK -- Unpack binary coded decimal	(68020+)

SYNOPSIS
	UNPK	-(Ax),-(Ay),#<adjustment>
	UNPK	Dx,Dy,#<adjustment>

	No size specs

FUNCTION
	Convert packed two-digit-per-byte BCD to byte-per-digit
	unpacked BCD.

FORMAT
	-----------------------------------------------------------------
	|15 |14 |13 |12 |11 |10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
	|---|---|---|---|-----------|---|---|---|---|---|---|-----------|
	| 1 | 0 | 0 | 0 |   Dy/Ay   | 1 | 1 | 0 | 0 | 0 |R/M|   Dx/Ax   |
	|---------------------------------------------------------------|
	|                    16 BITS ADJUSTMENT                         |
	-----------------------------------------------------------------

	R/M = 0 -> data register.
	R/M = 1 -> Memory by pre-decrementing.
	Register Dy/Ay specifies destination register.
	Register Dx/Ax specifies source register.
	"16 BITS ADJUSTMENT" is an immediate value added to source operand.

RESULT
	None.

SEE ALSO
	PACK