COPINS (cont.)
There are two indirect jump registers, COP1LC and COP2LC. These are 18-
bit pointer registers whose contents are used to modify the program
counter for initialization or jumps. They are transferred to the program
counter whenever strobe addresses COPJMP1 or COPJMP2 are written. In
addition, COP1LC is automatically used at the beginning of each vertical
blank time.
It is important that one of the jump registers be initialized and its
jump strobe address hit after power-up but before Copper DMA is
initialized. This insures a determined startup address and state.
COPJMP1 088 5 A Copper restart at first location
COPJMP2 08A 5 A Copper restart at second location
These addresses are strobe addresses. When written to, they cause the
Copper to jump indirect using the address contained in the first or
second location registers described below. The Copper itself can write to
these addresses, causing its own jump indirect.
- 270 Appendix A -
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