NAME	ROL, ROR -- Rotate left and rotate right
SYNOPSIS	ROd Dx,Dy ROd #<data>,Dy ROd <ea> where d is direction, L or R Size = (Byte, Word, Long)
FUNCTION	Rotate the bits of the operand in the specified direction. The rotation count may be specified in two different ways: Immediate - the rotation count is specified in the instruction Register - the rotation count is contained in a data register specified in the instruction For a register, the size may be byte, word, or long, but for a memory location, the size must be a word. The rotation count is also restricted to one for a memory location. . -------->-------- . ROL: | | C <------ OPERAND <--- ' <--- ROR: , -------<------- . | | ` --> OPERAND -----> C --->
FORMAT	In the case of the rotating of a register: 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 1 1 1 0 NUMBER/REGISTER dr SIZE i/r 1 1 REGISTER In the case of the rotating 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 1 1 dr 1 1 MODE REGISTER   <ea>
NUMBER/REGISTER	Specifies number of rotating or number of register which contents the number of rotating. If i/r = 0, number of rotating is specified in the instruction as immediate data If i/r = 1, it's specified in the data register. If dr = 0, right rotating If dr = 1, left rotating
SIZE	00 -> one Byte operation 01 -> one Word operation 10 -> one Long operation
REGISTER	For a register rotating: Indicates the number of data register on which rotating is applied. For a memory rotating: <ea> indicates operand which should be rotated. Only addressing modes relatives to memory are allowed: Addressing Mode Mode Register Dn - - An - - (An) 010 No reg. An (An)+ 011 No reg. An -(An) 100 No reg. An (d16,An) 101 No reg. An (d8,An,Xi) 110 No reg. An (bd,An,Xi) 110 No reg. An ([bd,An,Xi]od) 110 No reg. An ([bd,An],Xi,od) 110 No reg. An Addressing Mode Mode Register Abs.W 111 000 Abs.L 111 001 (d16,PC) - - (d8,PC,Xi) - - (bd,PC,Xi) - - ([bd,PC,Xi],od) - - ([bd,PC],Xi,od) - - #data - -
RESULT	X - Not affected 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.

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