COPCON 02E W A Copper control register
This is a 1-bit register that when set true, allows
the Copper to access the blitter hardware. This
bit is cleared by power-on reset, so that the
Copper cannot access the blitter hardware.
BIT NAME FUNCTION
01 CDANG Copper danger mode. Allows Copper
access to blitter if true.
COPINS 08C W A Copper instruction fetch identify
This is a dummy address that is generated by the
Copper whenever it is loading instructions into
its own instruction register. This actually occurs
every Copper cycle except for the second (IR2)
cycle of the MOVE instruction. The three types
of instructions are shown below.
MOVE - Move immediate to destination.
WAIT - Wait until beam counter is equal to, or
greater than. (keeps Copper off of bus
until beam position has been reached).
SKIP - Skip if beam counter is equal to or greater
than (skips following MOVE instruction unless
beam position has been reached).
- 268 Appendix A -
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