updates build instruction and SCC to latest version

README.md

@@ -4,16 +4,29 @@ A simple C++/SystemC/CMake project to test pysysc
 
 # How to build
 
-> Currently only Linux and MacOS are tested
+> Currently only Linux and MacOS are tested. 
 
+The install instruction below assume using bash.
 
 ```
+git clone --recursive -b develop https://git.minres.com/SystemC/PySysC-SC.git
 cd PySysC-SC
-mkdir build
-cd build
-conan install .. --build=missing
-cmake -DBUILD_SHARED_LIBS=ON ..
-cmake --build .
+python3 -mvenv .venv
+. .venv/bin/activate
+pip install "conan<2.0"
+cmake -S . -B build -DBUILD_SHARED_LIBS=ON -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
+cmake --build build -j24
+export SYSTEMC_HOME=$(grep -A1 rootpath_systemc\] build/conanbuildinfo.txt | tail -1)
+export STDCXX=17
+pip install "cppyy<3.0" 
+pip install https://github.com/Minres/PySysC/tarball/master
+pip install scc/contrib/pysysc/
+python3 router_example.py
+python3 router_example2.py
+python3 modules.py
 ```
 
-
+These steps clone the PySysC-SC repository and builds the shared libraries using conan 1.x.
+This also downloads and builds SYSTEMC (as a conan package).
+Then it installs the python packages cppyy, PySysC, and PySysC.SCC using the same settings as the cmake build.
+Eventually it runs the 3 examples.