BTST Instruction

This instruction will test a bit in an operand specified by an effective address. The Z-flag (the only flag affected) will be set as the bit was before the change! The bit number is stored in a data register or is an immediate address.

ADDRESS METHODS: Dn, (An), (An)+, -(An), x(An), x(An,xr.s), x.w, x.l, x(PC), x(PC,xr.s)

DATA LENGTH: Byte, longword

FLAGS: Z - Set if the bit was 0 before the change, else cleared. All other flags unaffected.

SYNTAX:	BTST Dn,<ea>
	BTST #<data>,<ea>