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Open questions

Should ALUMI sign extend the 8 bit quantity to 32 bits?

Same question for LOADLWI

The LOADM, STOREPCD etc format has 13 bits free. Should this be available for small immediate displacements? This would duplicate these instructions so could be expensive.

The branching formats have 8 bits free. This seems pretty useless for an immediate displacement in a 32 bit system, but am not totally sure.

How to deal with condition codes being stacked? This will be needed when interrupts are implemented. The push and pop formats have 4 bits free, so could be extended.

Manual manipulation of the condition bits is currently missing.

• Dedicated ANDCC/ORCC instruction like 6809?
• Or add a register swap?
• Or something else?