Arithmetic Shift Left and Arithmetic Shift Right

NAME
	ASL, ASR -- Arithmetic shift left and arithmetic shift right

SYNOPSIS
	ASd	Dx,Dy
	ASd	#<data>,Dy
	ASd	<ea>
	where d is direction, L or R

	Size = (Byte, Word, Long)

FUNCTION
	Performs an arithmetic shifting bit operation in the indicated
        direction, with an immediate data, or with a data register.
        If you shift address contents, you only can do ONE shift, and
        your operand is ONE word exclusively.

	ASL:              <--  
	      C <------ OPERAND <--- 0
	            |
	            |
	      X <---'
	       

	ASR:      -->
	  .---> OPERAND ------> C
          |    T          |
	  |    |          |
	  `----'          `---> X

FORMAT
	In the case of the shifting of a register:
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	-----------------------------------------------------------------
	|15 |14 |13 |12 |11 |10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
	|---|---|---|---|-----------|---|-------|---|---|---|-----------|
	| 1 | 1 | 1 | 0 |  NUMBER/  |dr |  SIZE |i/r| 0 | 0 | REGISTER  |
	|   |   |   |   |  REGISTER |   |       |   |   |   |           |
	-----------------------------------------------------------------

	In the case of the shifting of a memory area:
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	-----------------------------------------------------------------
	|15 |14 |13 |12 |11 |10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
	|---|---|---|---|---|---|---|---|---|---|-----------|-----------|
	| 1 | 1 | 1 | 0 | 0 | 0 | 0 |dr | 1 | 1 |    MODE   | REGISTER  |
	----------------------------------------=========================
	                                                  <ea>


NUMBER/REGISTER
	Specifies number of shifting or number of register which contents
	the number of shifting.
	If i/r = 0, number of shifting is specified in the instruction as
	immediate data
	If i/r = 1, it's specified in the data register.
	If dr = 0, right shifting
	If dr = 1, left shifting

SIZE
	00->one Byte operation
	01->one Word operation
	10->one Long operation

REGISTER
	For a register shifting:
	Indicates the number of data register on which shifting is applied.

	For a memory shifting:
	<ea> indicates operand which should be shifted.
	Only addressing modes relatives to memory are allowed:

	--------------------------------- -------------------------------
	|Addressing Mode|Mode| Register | |Addressing Mode|Mode|Register|
	|-------------------------------| |-----------------------------|
	|      Dn       | -  |     -    | |    Abs.W      |111 |  000   |
	|-------------------------------| |-----------------------------|
	|      An       | -  |     -    | |    Abs.L      |111 |  001   |
	|-------------------------------| |-----------------------------|
	|     (An)      |010 |N reg. An| |   (d16,PC)    | -  |   -    |
	|-------------------------------| |-----------------------------|
	|     (An)+     |011 |N reg. An| |   (d8,PC,Xi)  | -  |   -    |
	|-------------------------------| |-----------------------------|
	|    -(An)      |100 |N reg. An| |   (bd,PC,Xi)  | -  |   -    |
	|-------------------------------| |-----------------------------|
	|    (d16,An)   |101 |N reg. An| |([bd,PC,Xi],od)| -  |   -    | 
	|-------------------------------| |-----------------------------|
	|   (d8,An,Xi)  |110 |N reg. An| |([bd,PC],Xi,od)| -  |   -    |
	|-------------------------------| |-----------------------------|
	|   (bd,An,Xi)  |110 |N reg. An| |    #data      | -  |   -    |
	|-------------------------------| -------------------------------
	|([bd,An,Xi]od) |110 |N reg. An|
	|-------------------------------|
	|([bd,An],Xi,od)|110 |N reg. An|
	---------------------------------

RESULT
	X - Set according to the list bit shifted out of the operand.
	    Unaffected for a shift count of zero.
	N - Set if the most-significant bit of the result is set. Cleared
	    otherwise.
	Z - Set if the result is zero. Cleared otherwise.
	V - Set if the most significant bit is changed at any time during
	    the shift operation. Cleared otherwise.
	C - Set according to the list bit shifted out of the operand.
	    Cleared for a shift count of zero.

SEE ALSO
	ROd  ROXd

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