NAME	BFCHG -- Bit field change
SYNOPSIS	BFCHG <ea>{OFFSET:WIDTH} (68020+) No size specs.
FUNCTION	<ea> indicates destination operand which a part of bits have to be inverted. Offset enables to locate first bit of field; width specifies number of bits of this field. Field is tested, flags are set, and bits of field are inverted. 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 0 1 0 1 1 MODE REGISTER 0 0 0 0 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 range from 1 to 31, indicating a width from 1 to 31 bits. A value 0 indicates a width of 32 bits.
REGISTER	<ea> is always 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) - - (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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