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NAME BFINS -- Bit field insert
SYNOPSIS
BFINSDn,<ea>{OFFSET:WIDTH}(68020+)
No size specs.
FUNCTION <ea> indicates destination operand which field of bits have to be inserted. Offset enables to locate first bit of field; width specifies number of bits of this field.
Bit field from Dn, which must be inserted in destination operand, is located in relation to bit zero. This bit zero, after insert, will have for offset: base offset more (width - 1).
Be careful, this instruction operates from MSB to LSB!!
FORMAT
 <ea>
1514131211109876543210
1110111111MODEREGISTER
0REGISTERDoOFFSETDwWIDTH
If Do = 0->Field "OFFSET" contains an immediate value which represents effective offset, value from 0 to 31.
If Do = 1->Field "OFFSET" indicates number of a data register (bits 9 and 10 of field cleared) which contains effective offset. Signed value is represented on 32 bits., so it's extended from -2 EXP 31 to (+2 EXP 31) -1.

If Dw = 0->field "WIDTH" contains an immediate value between 1 and 31 which indicates a width from 1 to 31 bits. A value of 0 indicates a width of 32 bits.
If Dw = 1->field "WIDTH" indicates number of a data register (bits 3 and 4 of field cleared) which contains width of bit field. The value modulo 32 can go from 1 to 31, indicating a width from 1 to 31 bits. A value 0 indicates a width of 32 bits.

REGISTER <ea> specifies destination, addressing modes are the following:
Addressing ModeModeRegister
Dn000No reg. Dn
An--
(An)010No reg. An
(An)+--
-(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-not affected
N-Set if MSB of field is set. Cleared otherwise.
Z-Set if all the bits of the field tested are zero.
Cleared otherwise.
V-Always cleared.
C-Always cleared.


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Änderungen und Irrtümer vorbehalten. Letzte Änderung:
14 September 2001.
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