SYSTEM

Used Exports

	MODULE SYSTEM; (pseudo module declaring all the SYSTEM procedures )

	TYPE
	(* pseudo types used by the builtin procedures *)
	AnyType = RECORD (* any type *) END;
	TypeType = RECORD (* A type goes here, not a variable *) END;

	(* pseudo arrays representing the memory and the registers *)
	VAR mem, registers, specialregisters: ARRAY 0 OF INTEGER;

	PROCEDURE ADR *(VAR v: AnyType): INTEGER;
	BEGIN RETURN (* address of *) v
	END ADR;

	PROCEDURE SIZE *(VAR T: TypeType): INTEGER;
	BEGIN RETURN (* size of *) T
	END SIZE;

	PROCEDURE BIT *(a, n: INTEGER): BOOLEAN;
	BEGIN RETURN mem[a] = n (* th bit set*)
	END BIT;

	PROCEDURE GET *(a: INTEGER; VAR v: AnyType);
	BEGIN v := mem[a]
	END GET;

	PROCEDURE PUT *(a: INTEGER; x: AnyType);
	BEGIN mem[a] := x
	END PUT;

	PROCEDURE COPY *(src, dst, n: INTEGER);
	VAR i: INTEGER;
	BEGIN
	FOR i:= 0 TO n - 1 DO mem[dst + i] := mem[src + i] END
	END COPY;

	PROCEDURE VAL *(T: TypeType; n: AnyType): TypeType;
	BEGIN RETURN n (* identity converted to T *)
	END VAL;

	(* LDPSR, LDREG, REG, H, COND are not in language definition,
	but SYSTEM.COND is not used by Project Oberon *)

	PROCEDURE LDREG * (reg, value: INTEGER);
	BEGIN registers[reg] := value
	END LDREG;

	PROCEDURE LDPSR * (value: INTEGER);
	BEGIN (* enable / disable interrupts *)
	END LDPSR;

	PROCEDURE REG *(reg: INTEGER): INTEGER;
	BEGIN RETURN registers[reg]
	END REG;

	(* H(0) = remainder of last division; H(1) = processor cpuid *)
	PROCEDURE H *(reg: INTEGER): INTEGER;
	BEGIN RETURN specialregisters[reg]
	END H;

	END SYSTEM.