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NAME ROXL, ROXR -- Rotate left with extend and rotate right with extend
SYNOPSIS
ROXdDx,Dy
ROXd#<data>,Dy
ROXd<ea>
where d is direction, L or R
Size = (Byte, Word, Long)
FUNCTION A rotation is made on destination operand bits. Rotation uses bit X.
.-------->-----------.
ROXL:||
C<------ OPERAND <- X --'
<---
ROXR:,---------<-------.
||
`-- X -> OPERAND ----->C
--->
FORMAT In the case of the rotating of a register:
1514131211109876543210
1110NUMBER/REGISTERdrSIZEi/r10REGISTER
In the case of the rotating of a memory area:
1514131211109876543210
1110010dr11MODEREGISTER
 <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 ModeModeRegister
Dn--
An--
(An)010No reg. An
(An)+011No reg. An
-(An)100No reg. An
(d16,An)101No reg. An
(d8,An,Xi)110No reg. An
(bd,An,Xi)110No reg. An
([bd,An,Xi]od)110No reg. An
([bd,An],Xi,od)110No reg. An
Addressing ModeModeRegister
Abs.W111000
Abs.L111001
(d16,PC)--
(d8,PC,Xi)--
(bd,PC,Xi)--
([bd,PC,Xi],od)--
([bd,PC],Xi,od)--
#data--

RESULT
X-Set by the last bit out of operand. Not changed if rotation is zero.
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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Änderungen und Irrtümer vorbehalten. Letzte Änderung:
14 September 2001.
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