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cmpa

Compare address

Compares an address register with the first operand and sets the flags, sign extending a word to long.

Sizes .w .l, .w by default

XNZVC –●●●●
  • ● set from the result
  • – not changed

Forms

Operands

<ea>
An operand using one of the instruction’s supported addressing modes, such as d0, (a0)+ or 4(a1). It may name a register, memory or an immediate value. More
An
An address register, a0 to a7; sp is another name for a7. More
#imm
An immediate value written after #: a number, character or label, such as #10, #$FF or #'a'. It must fit the operation’s size: byte -128 to 255, word -32768 to 65535, or long -2147483648 to 4294967295; signed and unsigned spellings are accepted. More

When using word size, the first operand is sign extended to long and the second is read and written as a long.

lea $1000, a0
cmpa.l #$1000, a0
seq d0 ; d0 = $FF (equal)

lea $2000, a1
cmpa.l #$1000, a1
sgt d1 ; d1 = $FF ($2000 > $1000)