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Accessing the hardware

Java was developed as a save language. That is it does not allow direct access and manipulation of absolute memory locations. Nevertheless this is essential for embedded programming. We therefore include this possibility by the use a special Java class US.java (US stand for unsafe). Wenn methods of this class are used the code generator inserts machine code accordingly.
By using US.java you can

  • read from absolute memory locations (1, 2, 4, 8 bytes)
  • write to absolute memory locations (1, 2, 4, 8 bytes)
  • test a bit at an absolute memory location
  • read and write directly to machine registers (GPRs, FPRs, SPRs)
  • directly insert machine code
  • get the address of a static method at compile time
  • enable the use of floats for exception routines

The API of US.java can be found here: API US.java