Name: In-Circuit Debugger
ID: 0x4d6f6f6e
Version: 1

Interrupts do different things depending on contents of the A register:

 A | BEHAVIOR
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 0 | The B register is read, and the corresponding memory address is protected.
 1 | The B register is read, and the corresponding memory address is unprotected.
 2 | The B register is copied to the hardware breakpoint register
 3 | The hardware breakpoint register is copied to the B register
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Whenever PC is equal to the hardware breakpoint register, 
or an attempt is made by the DCPU or any peripheral 
to write to a protected memory address, DCPU execution 
is immediately halted. DCPU state may then be examined and execution
resumed by external mechanisms not covered by this spec.