NAME	BFFFO -- Bit field find first one set
SYNOPSIS	BFFFO <ea>{OFFSET:WIDTH},Dn (68020+) No size specs.
FUNCTION	<ea> indicates source operand which a part of bits have to be examined. Offset enables to locate first bit of field; width specifies number of bits of this field. Field is examined, offset of first bit set is encountred, the MSB is stored in the data register Dn. Offset is equal to base offset more offset of bit into examined field. If no bits set are found, data register Dn contains a value which follows to initial offset more width of bit field. Be careful, this instruction operates from MSB to LSB!!
FORMAT	<ea> 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 1 1 1 0 1 1 0 1 1 1 MODE REGISTER 0 REGISTER Do OFFSET Dw WIDTH 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 Mode Mode Register Dn 000 No reg. Dn An - - (An) 010 No reg. An (An)+ - - -(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) 111 010 (d8,PC,Xi) 111 011 (bd,PC,Xi) 111 011 ([bd,PC,Xi],od) 111 011 ([bd,PC],Xi,od) 111 011 #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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