NAME	BTST -- Bit test
SYNOPSIS	BTST Dn,<ea> BTST #<data>,<ea> Size = Byte, Long
FUNCTION	Tests a bit in the destination operand and sets the Z condition code appropriately. If the destination is a data register, any of the 32 bits can be specified by the modulo 32 number. When the distination is a memory location, the operation must be a byte operation, and therefore the bit number is modulo 8. In all cases, bit zero is the least significant bit. The bit number for this operation may be specified in either of two ways: 1. Immediate -- The bit number is specified as immediate data. 2. Register -- The specified data register contains the bit number.
FORMAT	In the case of BTST Dn,<ea>: 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 0 0 0 REGISTER 1 0 0 MODE REGISTER   <ea> In the case of BTST #<data,<ea>:   <ea> 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 0 0 0 1 0 0 0 0 0 MODE REGISTER 0 0 0 0 0 0 0 0 NUMBER OF THE BIT
REGISTER	In the case of BTST Dn,<ea>: <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)+ 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) 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 111 100 * Long only; for others modes: Byte only. In the case of BTST #<data,<ea>: Addressing Mode Mode Register Dn * 000 No reg. 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) 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 - not affected Z - Set if the bit tested is zero. Cleared otherwise. V - not affected C - not affected

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