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		Release Notes for SystemC Release 2.0.1
                =======================================

CONTENTS
========

  1) What's new in this release?

  2) Bug fixes and enhancements

  3) Other changes

  4) Known limitations

  5) Beta features

  6) Deprecated features

  7) Fixed-point library


1) What's new in this release?
==============================

Compared to the 2.0 Production release, this release has the following
new items:

  - Several bug fixes and enhancements. See Section 2) for details.

  - Several other code changes. See Section 3) for details.

  - The simple bus example, an example of modeling a bus at the
    transaction level. This example includes source code as well
    as detailed documentation.

  - From this release onwards, a SystemC regression test suite is also
    released (separately).


2) Bug fixes and enhancements
=============================

Following is the list of bug fixes and enhancements for this release:

  - (104531) Fixed-point datatypes need more information.
  - (105656) Need explanation when to use end_module()
  - (125720) Need to document resolution of resolved vector signals
  - (126722) concatination operator errors out on more than 16 arguments
  - (129353) memory leak in fixed-point slicing operators
  - (129901) Link failure: some sc_fxval methods are declared but not impl
  - (129933) sc_bit declares many methods that are not defined
  - (130513) compilation error when including iostream.h before systemc.h
  - (130782) part select on sc_biguint produces wrong result in cornercase
  - (130786) code doesn't compile with gcc-2.95.2
  - (131145) library compilation error with -DDEBUG_SYSTEMC
  - (132075) Comparison of sc_[u]int bit-slices does not work
  - (132136) inconsistency: sc_bv.range()=int not allowed
  - (132137) sc_bv & int does not work
  - (132221) bug in QuickThreads code (sparc.s) when using -fast
  - (133377) sc_bigint::operator(,) gives wrong results
  - (135336) Syntax error in hierarchical channel example in func spec docu
  - (135767) bogus sc_logic assignment
  - (135771) range method with sc_lv doesn't work
  - (137040) bool sc_uint_base::operator[](int) const, bug ?
  - (137233) stream I/O for sc_bigint and sc_biguint cannot be used
  - (137234) The SystemC library should never call abort()
  - (138408) sc_bit x = my_sc_bv[0] doesn't compile


3) Other changes
================

Here is an overview of changes with respect to 2.0 Production:

  - When used with signals, a user-defined type _must_ define
    the following operators:

      o T& operator = ( const T& );                  // assignment
      o bool operator == ( const T& );               // comparison
      o ostream& operator << ( ostream&, const T& ); // output streaming

    If (and only if) a user-defined type is used in tracing, the
    following function _must_ also be defined:

      o void sc_trace( sc_trace_file*, const T&, const sc_string& );

    The SystemC code has been changed such that the sc_trace() function
    is only required if it is actually used.

  - On Windows NT 4.0 and Windows 2000, the SC_VC6_SCL macro didn't work
    in 2.0 Production. This macro was used in earlier releases of SystemC
    to enable the use of Standard Class Library header files, such as
    <vector>. The SystemC code has been changed such that Standard Class
    Library header files can be included _without_ setting the SC_VC6_SCL
    macro. The systemc.h header file takes care of including <iostream>,
    <strstream>, and <fstream>. Because <iostream.h>, <strstrea.h>, and
    <fstream.h> (on Windows) cannot be combined with the above header
    files, one should avoid including these header files.

  - All datatypes and supporting types are now put in the 'sc_dt' namespace.
    The 'sc_bv_ns' namespace, in which the bit types (e.g. sc_bv, sc_lv)
    used to reside, has been removed and replaced with the 'sc_dt' namespace.
    The systemc.h header files "exports" most datatypes (e.g.
    'using sc_dt::sc_bv'). In case you cannot access a certain datatype,
    try 'sc_dt::type'.

  - Concatenation is now also possible with the 'concat()' function. For
    all datatypes for which concatentation was defined with 'operator , ()',
    now also the two-argument 'concat()' function is defined.

  - Concatentation is still _not_ possible for the arbitrary size integer
    datatypes sc_big[u]int and their base classes sc_[un]signed. Dummy
    functions have been put into place to avoid that 'operator ,()' on
    these types falls back to the C++ list operator. But when you use
    concatenation on these types, you will get a run-time "not implemented"
    error.

  - A number of methods and types related to the datatypes are now
    deprecated (in order better to align with the VSIA datatypes "standard").
    For these deprecated methods and types there are alternatives. In case
    you want to use a deprecated method or type, you can define the
    SC_DT_DEPRECATED macro.

    Some of the deprecated methods and types (left deprecated, right the
    alternative you should use instead):

      o sc_logic_0     ->  SC_LOGIC_0
      o sc_logic_1     ->  SC_LOGIC_1
      o sc_logic_Z     ->  SC_LOGIC_Z
      o sc_logic_X     ->  SC_LOGIC_X
      o to_signed()    ->  to_int()
      o to_unsigned()  ->  to_uint()

  - String input and output for the bitvector types and the integer types
    has been improved. They now support all number representations as
    already supported by the fixed-point types. The bitvector types behave
    slightly different, because the default number representation is still
    binary, whereas for the integer and fixed-point types this is decimal.

    BEWARE:
      Due to the extended support of number representations in string
      input and output, "0x" and "0X" are no longer valid as start of
      a logic character string, because this is seen as a hexadecimal
      number representation prefix! In this case, add a "0" in front
      (to get "00x" and "00X"). E.g.

        sc_lv<4> a;
        a = "0XX1";  // error
        a = "00XX1"; // ok

    String output with the to_string() function takes zero, one or two
    arguments (in most cases). The (optional) first argument is of
    type sc_numrep and indicated the required number representation.
    The (optional) second argument is of type bool and indicated if
    a prefix should be added (default true).

  - The limited precision integer types sc_[u]int and their base classes
    sc_[u]int_base now have the reduce functions defined. These are:

      o and_reduce()
      o nand_reduce()
      o or_reduce()
      o nor_reduce()
      o xor_reduce()
      o xnor_reduce()

    In addition, also length checks have been added for the limited precision
    integer types.

  - When including systemc.h, you can use the sc_min(), sc_max(), or sc_abs()
    functions to calculate the minimum, maximum, or absolute value of some
    datatype value(s). You can use these functions with SystemC datatypes,
    with C/C++ native types, or with you own datatypes.

  - Positive and negative edges have now also been defined for signals of
    type sc_logic. The definition of positive and negative is exactly like
    in VHDL or Verilog (a positive edge is any non-one to one transition,
    and a negative edge is any non-zero to zero transition).

  - The signal ports now also define the event access methods of their
    respective interfaces. You can write in a module, e.g.

      wait( in_port.value_changed_event() );

  - The build process has been changed such that only a C++ compiler is
    needed to compile the SystemC object code library. In 2.0 Production,
    the QuickThreads code is compiled with a C compiler. In 2.0.1,
    this code is also compiled with the C++ compiler.

  - On HP-UX, you must additionally use the '-ext' compiler flag to
    compile you code. You can find the full set of compiler flags in
    the configure.in file that comes with the distribution (search for
    hpux11 and take the flags in EXTRA_CXXFLAGS).

  - This release comes with a changed (error) reporting scheme. In 2.0
    Production, there were several error reporting mechanisms, none of
    which are also user configurable. In this release, a (error)
    reporting scheme is provided that can also be extended by the user.
    In addition, debugging your design in the presence of SystemC warnings
    or errors has been made easier.

      o Introduction

        In SystemC, report messages come with an id and a severity. There
        are four severities: SC_INFO, SC_WARNING, SC_ERROR, and SC_FATAL.
        There are a number of ids predefined by SystemC (everthing below
        1000). Each id comes with a standard message text, and when invoked,
        a report can add some additional message text.

        A report id is registered with 'sc_report::register_id(id,msg)',
        which registers the id and the standard message text. A report
        is generated with SC_REPORT_INFO(id,msg), SC_REPORT_WARNING(id,msg),