Merge pull request #682 from theotherjimmy/arm-compiler-switching

Document Arm Compiler switching based on arch version

Author: Amanda Butler

docs/tools/offline/cli-compile.md

@@ -37,7 +37,8 @@ Image: BUILD/K64F/GCC_ARM/mbed-os-program.bin
 The arguments for *compile* are:
 
 - `-m <MCU>` selects a target. If `detect` or `auto` parameter is passed to `-m`, then Mbed CLI detects the connected target.
-- `-t <TOOLCHAIN>` selects a toolchain (of those defined in `mbed_settings.py`, see above). The value can be `ARM` (Arm Compiler 5), `GCC_ARM` (GNU Arm Embedded) or `IAR` (IAR Embedded Workbench for Arm).
+- `-t <TOOLCHAIN>` selects a toolchain defined in `mbed_settings.py`. The value can be `ARM` (Arm Compiler), `GCC_ARM` (GNU Arm Embedded) or `IAR` (IAR Embedded Workbench for Arm).
+   <span class="notes">**Note**: `mbed compile -t ARM` selects the Arm Compiler major version based on the Arm architecture version of your target. Arm architecture versions 6 and 7 use Arm Compiler 5, and Arm architecture version 8 uses Arm Compiler 6.</span>
 - `--source <SOURCE>` selects the source directory. The default is `.` (the current directory). You can specify multiple source locations, even outside the program tree.
 - `--build <BUILD>` selects the build directory. Default: `BUILD/` inside your program root.
    <span class="notes">**Note**: `mbed compile` ignores the current build directory; creating multiple build directories leads to errors.</span>

docs/tools/offline/cli-setup.md

@@ -25,9 +25,7 @@ For Linux, please [install Mbed CLI manually](installing-manually.html). Advance
     - [Git](https://git-scm.com/) - version 1.9.5 or later.
     - [Mercurial](https://www.mercurial-scm.org/) - version 2.2.2 or later.
 
-- **Command-line compiler or IDE toolchain:** Mbed CLI invokes the [Mbed OS 5](https://github.com/ARMmbed/mbed-os) tools for various features, such as compiling, testing and exporting to industry standard toolchains. To compile your code, you need either a compiler or an IDE:
-    - Compilers: Arm GCC, Arm Compiler 5, IAR.
-    - IDE: Keil uVision, DS-5, IAR Workbench.
+- **Command-line compiler:** Mbed CLI invokes the [Mbed OS 5](https://github.com/ARMmbed/mbed-os) tools for various features, such as compiling, testing and exporting to industry standard toolchains. To compile your code, you need one of the following compilers: GCC Arm, Arm Compiler 5, Arm Compiler 6 and IAR.
 
     <span class="notes">**Note:** When installing the Arm Compiler 5 on a 64-bit Linux machine, you may need to also install the i386 architecture package:</span>