NAME	CLR -- Clear
SYNOPSIS	CLR <ea> Size = (Byte, Word, Long)
FUNCTION	Clears the destination operand to zero. On an MC68000 and MC68HC000, a CLR instruction does both a read and a write to the destination. Because of this, this instruction should never be used on custom chip registers.
FORMAT	15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 1 0 0 0 0 1 0 SIZE MODE REGISTER   <ea>
REGISTER	<ea> specifies destination operand, addressing modes allowed are: 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) - - (d8,PC,Xi) - - (bd,PC,Xi) - - ([bd,PC,Xi],od) - - ([bd,PC],Xi,od) - - #data - -
SIZE	00 -> one Byte operation 01 -> one Word operation 10 -> one Long operation
RESULT	X - Not affected N - Always cleared Z - Always set V - Always cleared C - Always cleared

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