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As a coprocessor, the Copper adds its own instruction set to the
instructions already provided by the 680x0 CPU. The Copper has only three
instructions, but you can do a lot with them:

*   WAIT  for aspecific screen position specified as x and y coordinates.

*   MOVE  animmediate data value into one of the special-purpose

*   SKIP . the next instruction if the video beam has already reached
   a specified screen position.

All Copper instructions consist of two 16-bit words in sequential memory
locations. Each time the Copper fetches an instruction, it fetches both

The  MOVE  and  SKIP . instructions require two memory cycles and two
instruction words each. Because only the odd memory cycles are requested by
the Copper, four memory cycle times are required per instruction.  The
 WAIT  instruction requires three memory cycles and six memory cycle
times; it takes one extra memory cycle to wake up.

Although the Copper can directly affect only machine registers, it can also
affect memory indirectly by setting up a blitter operation.  More
information about how to use the Copper in controlling the blitter can be
found in the sections called  Control Register  and
 Using the Copper with the Blitter .

The  WAIT  and  MOVE  instructions are described below. The  SKIP 
instruction is described in the "Advanced Topics" section.

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