Logical Shift Left and Logical Shift Right

NAME
	LSL, LSR -- Logical shift left and logical shift right

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

	Size = (Byte, Word, Long)

FUNCTION
	Shift the bits of the operand in the specified direction.
	The carry bit set set to the last bit shifted out of the operand.
	The shift count for the shifting of a register may be specified in
	two different ways:

	1. Immediate - the shift count is specified in the instruction (shift
	               range 1-8).
	2. Register  - the shift count is contained in a data register
	               specified in the instruction (shift count mod 64)

	For a register, the size may be byte, word, or long, but for a memory
	location, the size must be a word. The shift count is also restricted
	to one for a memory location.

	LSL:              <--  
	      C <------ OPERAND <--- 0
	            |
	            |    (V = 0)
	      X <---'
	       

	LSR:
                 -->
	0 ---> OPERAND -------> C
                          |
	                  |
	                  `---> 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 | 1 | 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 | 1 |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 last bit shifted out of the operand.
	N - Set if the result is negative. Cleared otherwise.
	Z - Set if the result is zero. Cleared otherwise.
	V - Always cleared
	C - Set according to the last bit shifted out of the operand.

SEE ALSO
	ASL, ASR	ROL, ROR

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