maehne

Thanks @Asdruv for reporting this bug! I have forwarded your report to the LWG. Best regards, Torsten Maehne

sc_core::sc_in<T> only allows binding of a single sc_core::sc_signal<T> (cf. to IEEE Std 1666-2011, clause 6.8). However, you may use for in_B a sc_core::sc_port<sc_core::sc_signal_in_if<T>, 3, SC_ONE_OR_MORE_BOUND> (cf. to IEEE Std 1666-2011, clause 5.12) that will accept binding of exactly three signals. The implementation of the OR relation of the three signals can be then handled inside an SC_METHOD of objB. To access the three different signal from in_B, you can use the operator[] implemented by the sc_port. By the way, you may also specify a different number of channels to be bound and also a different port binding policy.

If you don't use the member functions added that were added for convenience to `sc_in`, `sc_out`, and `sc_inout` to, e.g., call `read()`, `write()`, and the event member functions via the `.` operator than via the corresponding member function in the interface accessed via the `->` operator, you might be able to avoid entirely the derivation of new port classes. Instead, you could simply use a template alias, which was introduced with C++'11: template<typename T> using sc_in_opt = sc_core::sc_port<sc_signal_in_if<T>, 1, SC_ZERO_OR_MORE_BOUND>; template<typename T> using sc_inout_opt = sc_core::sc_port<sc_signal_inout_if<T>, 1, SC_ZERO_OR_MORE_BOUND>; template<typename T> using sc_out_opt = sc_core::sc_port<sc_signal_inout_if<T>, 1, SC_ZERO_OR_MORE_BOUND>; If you want to also provide all member functions of `sc_in`, `sc_out`, and `sc_inout`, you will have to derive from the `sc_port` class and implement the full interface as defined in IEEE Std 1666-2011.

This output does not hint for any problem. What output do you expect from your alu model? You need to implement explicitly any debug output in your SystemC model using, e.g., the SC_REPORT_* macros. Tracing of signal using the sc_trace() mechanism won't cause any additional output on the console either. If you expect some output, you will have to share the code of a minimal working example exposing your problem. Your CMakeLists.txt looks mostly fine. However, it contains several unnecessary lines. After finding SystemC using find_package, you only need to make sure that your executable target is linked against the SystemC::systemc target using the target_link_libraries(alu SystemC::systemc) call. CMake retrieves from this target automatically any necessary compiler flags, preprocessor definitions, include paths, and library paths, which previously needed to be set up by hand. So, your minimal CMake file could look something like: cmake_minimum_required(VERSION 3.1) project(alu) find_package(SystemCLanguage CONFIG REQUIRED) # # Setting the C++ standard from the SystemC_CXX_STANDARD variable may be still # # needed to compile without. So, in case of errors, try to uncomment the # # following two set (...) commands. The experimental CMake-based build system # # of the SystemC PoC implementation needs some updates to simplify further # # building SystemC application using CMake by using features introduced in # # CMake >3.11, which enable specifying even better the build and usage requirements # # of a library or executable. # set (CMAKE_CXX_STANDARD ${SystemC_CXX_STANDARD} CACHE STRING "C++ standard to build all targets. Supported values are 98, 11, and 14.") # set (CMAKE_CXX_STANDARD_REQUIRED ${SystemC_CXX_STANDARD_REQUIRED} CACHE BOOL # "The with CMAKE_CXX_STANDARD selected C++ standard is a requirement.") add_executable(alu main.cpp testbench.cpp) target_link_libraries(alu SystemC::systemc) The Section 4 of cmake/INSTALL_USING_CMAKE file contains some more hints.

Your calls to the configure script don't include the option --prefix to specify the destination directory for installation. This is strongly recommended as the SystemC installation layout does not match well with the standard Unix directory layout for a conflict-free installation. Personally, I prefer to install SystemC on Unix-like platforms to /opt/systemc-2.3.3 (or similar). After make install, you can make sure that the include and lib-* directory below the prefix contains the necessary files. When building against this SystemC version, you will have to pass the proper include and linker flags. I recommend that you read the INSTALL and RELEASENOTES files, which are part of the SystemC PoC implementation. You may also consider to use the experimental CMake-based build system instead of the autotools.

Before implementing your own ports and attempting to modify the SystemC code, you should first get familiar with the basic concepts and capabilities of SystemC. I suggest that you read a good introductory text to SystemC, e.g., "SystemC from the Ground Up" by David Black et al. That said, your requirement description seems to indicate that you could achieve the wanted functionality by using simply the standard SystemC ports and signals: One instance of sc_core::sc_out<T> in some module, which drives the global signal of type sc_core::sc_signal<T> that is bound to it during elaboration. And n port instances of sc_core::sc_in<T> bound to the same signal. You can then make some SC_METHOD or SC_THREAD in the module which instantiates one or several of this in ports to be sensitive to changes on this/these ports.

The SystemC libraries and their associated headers are usually not installed into the standard locations (/usr/lib/ and /usr/include/), where they would be found automatically by the compiler and linker. Instead, they are typically installed into their own directory hierarchy, e.g., below /opt/systemc-2.3.1/. Therefore, you need to indicate their location explicitly to the compiler and linker by passing the appropriate flags, e.g.: $ c++ -o my_tb my_tb.cpp -I/opt/systemc-2.3.1/include -L/opt/systemc-2.3.1/lib-linux -lsystemc Due to this, you also usually include the SystemC header using #include "systemc" to indicate that it is not a standard system header. I suggest that you first test your SystemC installation by compiling, linking, and running a pure SystemC example (e.g., the single-file simple_perf example, which is distributed as part of the SystemC PoC implementation in the directory examples/sysc/simple_perf/). From your questions, it seems that you are not particularly familiar with C++ and the associated toolchains. I would recommend that you first learn about them before focusing on SystemC and then Nigram.

Either you as the library author or the user of that library will need to provide at least an empty implementation of sc_main() to satisfy the linker. There is no way around it. I would like to also suggest that you update your SystemC installation to the latest version 2.3.3.

value_changed_event() returns a constant reference to an sc_core::sc_event. A SystemC method or thread can be made sensitive to that event to get activated each time the corresponding sc_event gets notified. Easiest would be to connect your sc_signals to matching sc_in port of a dedicated module, which sets up the method or thread responsible for counting your bit changes. I recommend that you read a good introduction to the basic concepts of SystemC, e.g., David C. Black et al. "SystemC from the Ground Up", 2nd ed. The SystemC elaboration and simulation semantics are also described in clause 4 of the freely available IEEE Std 1666-2011. If you are not yet much familiar with C++ itself, it might be a good idea to get first familiar with the fundamental concepts of C++ first.

The implementation of the TLM proof-of-concept library depends on SystemC. Therefore, you will need to link your application, which makes use of TLM, to the SystemC library. You can check it yourself by looking into the corresponding TLM headers: They include headers that are part of the SystemC implementation. Furthermore, the TLM implementation is not anymore header-only. The compiled .cpp implementation files are directly linked into the SystemC library file.

Thanks for reporting this bug! I forwarded it to the SystemC Language Working Group, so that it can be fixed for the next release of the SystemC proof-of-concept library.

@AvritSase: Your answer is unrelated to the issue discussed in this thread.

Glad I could help! You have grasped the idea correctly.

To achieve activation of your TDF controller only once per 5 activations of the valve and water tank modules, you will need to assign in addition to the time step also consistent rates to the TDF ports. E.g., you could assign to the TDF controller outputs command and threshold a rate of 5. Then, the connected valve and water tank modules will be activated 5 times per activation of the controller. As then the water tank will also output 5 times a water level sample to be read by the controller module, you will also need to assign a rate of 5 to the controller's input port. At this point, the TDF cluster is still not schedulable, as you have a feedback loop, which requires the insertion of a proper number of delay samples to achieve causality. To this end, you could, e.g., assign a delay of 5 to the controller input. For better understanding of the basic concepts of TDF modeling, I strongly suggest that you read at least the section 2.1 "Modeling fundamentals" of the SystemC AMS User's Guide available from the Accellera website.

@Martin Barnasconi is of course right about that there is no SCA_ELN_MODULE macro defined in the SystemC AMS standard, as it is currently not possible to define own primitive ELN modules. Personally, I prefer to avoid the use of preprocessor macros in C++ as much as possible -- especially when a fully equivalent concise proper C++ syntax exist. In the context of SystemC (AMS) the macros SC_MODULE, SCA_TDF_MODULE, SC_CTOR, and SCA_CTOR obfuscate in my humple opinion more the code than they help to render SystemC models more readable. Your class LifELN is very probably a class derived from sc_core::sc_module (SC_MODULE) and which contains the netlist of your ELN model (i.e., a circuit of ELN primitives). The time step needs to be set always on at least one instance of a primitive SystemC AMS module, which is part of a cluster of connected SystemC AMS primitive modules. Therefore, your second approach: is the correct one.