NAME   rev ADDR type chip Description
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COPCON h  02E  W     A    Coproccessor control register

         This is a-1 bit register that when set true, allows the coprocessor
         to access the blitter hardware. This bit is cleared power on reset,
         so that the coprocessor cannot access the blitter hardware.

         +------+-------+-------------------------------------------------+
         | BIT# | NAME  | FUNCTION                                        |
         +------+-------+-------------------------------------------------+
         | 01   | CDANG | Coprocessor danger mode. Allows coprocessor     |
         |      |       | access to all RGA registers if true.            |
         |      |       | (if 0, access to RGA>7E)                        |
         |      |       | (On old chips access to only RGA>3E if CDANG=1) |
         |      |       | (see VPOSR)                                     |
         +------+-------+-------------------------------------------------+