Add instructions to modify the template

README.md

@@ -13,7 +13,7 @@ More specifically:
 * instructions to get this repository locally are available in the [Create a SpinalHDL project](https://spinalhdl.github.io/SpinalDoc-RTD/master/SpinalHDL/Getting%20Started/Install%20and%20setup.html#create-a-spinalhdl-project) section.
 
 
-## TL;DR Things have arleady been set up in my environment, how do I run things to try SpinalHDL?
+### TL;DR Things have arleady been set up in my environment, how do I run things to try SpinalHDL?
 
 Once in the `SpinalTemplateSbt` directory, when tools are installed, the commands below can be run to use `sbt`.
 
@@ -34,6 +34,34 @@ sbt "runMain projectname.MyTopLevelSim"
 When you really start working with SpinalHDL, it is recommended (both for comfort and efficiency) to use an IDE, see the [Getting started](https://spinalhdl.github.io/SpinalDoc-RTD/master/SpinalHDL/Getting%20Started/index.html).
 
 
+## If you want to create a new project from this template
+
+### Change project name
+
+You might want to change the project name, which is currently `projectname`. To do so (let's say your actual project name is `myproject`; it must be all lowercase with no separators):
+
+* Update `build.sbt` and/or `build.sc` by replacing `projectname` by the name of your project `myproject` (1 occurrence in each file). The better is to replace in both (it will always work), but in some contexts you can keep only one of these two files:
+    * If you are sure all people only use `sbt`, you can replace only in `build.sbt` and remove `build.sc`
+    * If you are sure all people only use `mill`, you can replace only in `build.sc` and remove `build.sbt`
+    * Replace in both files for open-source project.
+* Put all your scala files into `hw/spinal/myproject/` (remove the unused `hw/spinal/projectname/` folder)
+* Start all your scala files with `package myproject`
+
+
+### Change project structure
+
+You can change the project structure as you want. The only restrictions (from Scala environment) are (let's say your actual project name is `myproject`):
+
+* you must have a `myproject` folder and files in it must start with `package myproject`
+* if you have a file in a subfolder `myproject/somepackage/MyElement.scala` it must start with `package myproject.somepackage`.
+* `sbt` and `mill` must be run right in the folder containing their configurations (recommended to not move these files)
+
+Once the project structure is modified, update configurations:
+
+* In `build.sbt` and/or `build.sc` (see above) replace `/ "hw" / "spinal"` by the new path to the folder containing the `myproject` folder.
+* In the spinal configuration file (if you kept it, by default it is in `projectname/Config.scala`) change the path in `targetDirectory = "hw/gen"` to the directory where you want generated files to be written. If you don't use a config or if it doesn't contain this element, generated files will be written in the root directory.
+
+
 ## Mill Support (Experimental)
 
 The [Mill build tool](https://com-lihaoyi.github.io/mill) can be installed and used instead of `sbt`.