STM3220G-EVAL: Update README.txt file describing how to build using the IAR toolchain

configs/stm3220g-eval/README.txt

@@ -185,6 +185,90 @@ IDEs
   one time from the Cygwin command line in order to obtain the pre-built
   startup object needed by RIDE.
 
+  Export nuttx to IAR or uVision workspace
+  ----------------------------------------
+  The script nuttx/toos/ide_exporter.py will help to create nuttx project in
+  these IDEs.  Here are few simple the steps to export the IDE workspaces:
+
+  1) Start the NuttX build from the Cygwin command line before trying to
+     create your project by running:
+
+       make V=1 |& tee build_log
+
+     This is necessary to certain auto-generated files and directories that
+     will be needed.   This will provide the build log to construct the IDE
+     project also.
+
+  2) Export the IDE project base on that make log. The script usage:
+
+     usage: ide_exporter.py [-h] [-v] [-o OUT_DIR] [-d] build_log {iar,uvision_armcc,uvision_gcc} template_dir
+
+     positional arguments:
+       build_log             Log file from make V=1
+       {iar,uvision_armcc,uvision_gcc}
+                             The target IDE: iar, uvision_gcc, (uvision_armcc is experimental)
+       template_dir          Directory that contains IDEs template projects
+
+     optional arguments:
+       -h, --help            show this help message and exit
+       -v, --version         show program's version number and exit
+       -o OUT_DIR, --output OUT_DIR
+                             Output directory
+       -d, --dump            Dump project structure tree
+
+     Example:
+        cd nuttx
+        make V=1 |& tee build_log
+
+        ./tools/ide_exporter.py makelog_f2nsh_c  iar ./configs/stm3220g-eval/ide/template/iar -o ./configs/stm3220g-eval/ide/nsh/iar
+
+        or
+
+        ./tools/ide_exporter.py makelog_f2nsh_c  uvision_gcc ./configs/stm3220g-eval/ide/template/uvision_gcc/ -o ./configs/stm3220g-eval/ide/nsh/uvision
+
+  3) Limitations:
+     - iar supports C only. Iar C++ does not compatible with g++ so disable
+       C++ if you want to use iar.
+     - uvision_armcc : nuttx asm (inline and .asm) can't be compiled with
+       armcc so do not use this option.
+     - uvision_gcc : uvision project that uses gcc. Need to specify path to
+       gnu toolchain.
+       In uVison menu, select:
+
+         Project/Manage/Project Items.../FolderExtension/Use GCC compiler/ PreFix, Folder
+
+  4) Template projects' constrains:
+     - mcu, core, link script shall be configured in template project
+     - Templates' name are fixed:
+        - template_nuttx.eww  : iar nuttx workspace template
+        - template_nuttx_lib.ewp : iar nuttx library project template
+        - template_nuttx_main.ewp : iar nuttx main project template
+        - template_nuttx.uvmpw : uVision workspace
+        - template_nuttx_lib.uvproj : uVision library project
+        - template_nuttx_main.uvproj : uVision main project
+     - iar:
+        - Library option shall be set to 'None' so that iar could use nuttx libc
+        - __ASSEMBLY__ symbol shall be defined in assembler
+     - uVision_gcc:
+        - There should be one fake .S file in projects that has been defined __ASSEMBLY__ in assembler.
+        - In Option/CC tab : disable warning
+        - In Option/CC tab : select Compile thump code (or Misc control = -mthumb)
+        - template_nuttx_lib.uvproj shall add 'Post build action' to copy .a file to .\lib
+        - template_nuttx_main.uvproj Linker:
+          - Select 'Do not use Standard System Startup Files' and 'Do not use Standard System Libraries'
+          - Do not select 'Use Math libraries'
+          - Misc control = --entry=__start
+
+    5) How to create template for other configurations:
+        1) uVision with gcc toolchain:
+            - Copy 3 uVision project files
+            - Select the MCU for main and lib project
+            - Correct the path to ld script if needed
+        2) iar:
+            - Check if the arch supportes iar (only armv7-m is supprt iar now)
+            - Select the MCU for main and lib project
+            - Add new ld script file for iar
+
 NuttX EABI "buildroot" Toolchain
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