MPY: Difference between revisions

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'''MPY''' is an assembly instruction. It multiply the contents of the memory location pointed to by the [[effective address]] with the
'''MPY''' is an assembly instruction. It multiplies the contents of the memory location pointed to by the [[effective address]] with the
contents of the [[A register]], leaving the result in the A register.
contents of the [[A register]], leaving the result in the A register.


== Flags affected ==
== Flags affected ==
If an overflow occurs, that is if the result has an absolute value greater than 32767<sub>10</sub>,  
If an overflow occurs, that is if the result has an absolute value greater than 32767<sub>10</sub>,  
both the [[dynamic overflow indicator]] ('''O''') and the [[static overflow indicator]] ('''Q''') are set to one.  
both the [[dynamic overflow indicator]] ('''Q''') and the [[static overflow indicator]] ('''O''') are set to one.  





Latest revision as of 13:12, 31 May 2010

MPY
Description Multipy integer
Format MPY <addr. mode> <disp.>
Code 120 0008
Affected A:=A*(ea), O, Q
Type User
Architecture ND-100, ND-110

MPY is an assembly instruction. It multiplies the contents of the memory location pointed to by the effective address with the contents of the A register, leaving the result in the A register.

Flags affected

If an overflow occurs, that is if the result has an absolute value greater than 3276710, both the dynamic overflow indicator (Q) and the static overflow indicator (O) are set to one.


References