Add compile cmake file and instructions.

CMakeLists.txt

@@ -0,0 +1,8 @@
+file(GLOB SOURCES *.c *.cpp "src" "src/base" "src/Fonts" "src/freetype" "src/sfnt" "src/smooth" "src/truetype" "src/utility")
+file(GLOB HEADERS "src" "src/base" "src/Fonts" "src/Fonts/Custom" "src/Fonts/GFXFF" "src/freetype" "src/freetype/config" "src/freetype/internal" "src/sfnt" "src/smooth" "src/truetype" "src/utility")
+set(requires "driver" "arduino-esp32")
+
+idf_component_register(SRCS ${SOURCES}
+                    INCLUDE_DIRS . ${HEADERS}
+                    REQUIRES ${requires}
+)

README.md

@@ -110,8 +110,201 @@ Resolution：540*960
 
 For more info on specific pin functions refer to the official ESP32 Docs[ESP32 datasheet](https://m5stack.oss-cn-shenzhen.aliyuncs.com/resource/docs/datasheet/core/esp32_datasheet_en.pdf)
 
+
+## How to compile it
+
+### For Windows
+
+1. Install [ESP-IDF v4.4][esp-idf-windows-installer]. For further info, read: [ESP-IDF Getting Started for Windows][esp-idf-windows-setup]
+
+   * Either the Online or Offline version shoud work
+   * When asked which components to install, don't change anything. Default options are Ok.
+   * When asked whether ESP can modify the system, answer "Yes"
+
+2. Launch the "ESP-IDF v4.4 CMD" (type that in the Windows search box)
+
+3. From the ESP-IDF cmd, clone the template
+
+   ```sh
+   git clone --recursive https://github.com/icyqwq/OLEDTrueType.git my_project
+   ```
+
+4. Compile it
+
+    ```sh
+    # Compile it
+    cd my_project
+    idf.py build
+
+    # Flash + open debug terminal
+    idf.py flash monitor
+    ```
+
+[esp-idf-windows-setup]: https://docs.espressif.com/projects/esp-idf/en/latest/esp32/get-started/windows-setup.html
+[esp-idf-windows-installer]: https://dl.espressif.com/dl/esp-idf/?idf=4.4
+
+### For Linux / macOS
+
+1. Requirements and permissions
+
+    Install ESP-IDF dependencies (taken from [here][toolchain-deps]):
+
+    ```sh
+    # For Ubuntu / Debian
+    sudo apt-get install git wget flex bison gperf python3 python3-pip python3-setuptools cmake ninja-build ccache libffi-dev libssl-dev dfu-util libusb-1.0-0
+    ```
+
+    And in case you don't have permissions to open `/dev/ttyUSB0`, do:
+    (taken from [here][ttyusb0])
+
+    ```sh
+    # You MUST logout/login (or in some cases reboot Linux) after running this command
+    sudo usermod -a -G dialout $USER
+    ```
+
+2. Install and setup ESP-IDF
+
+    ```sh
+    # Needs to be done just once
+    # Clone the ESP-IDF git repo
+    mkdir ~/esp && cd ~/esp
+    git clone -b release/v4.4 --recursive https://github.com/espressif/esp-idf.git
+
+    # Then install the toolchain
+    cd ~/esp/esp-idf
+    ./install.sh
+    ```
+
+3. Compile the template
+
+    Clone the template:
+
+    ```sh
+    # Do it everytime you want to start a new project
+    # Clone the template somewhere
+    mkdir ~/src && cd ~/src
+    git clone --recursive https://github.com/icyqwq/OLEDTrueType.git my_project
+    ```
+
+    Export the ESP-IDF environment variables in your shell:
+
+    ```sh
+    # Do it everytime you open a new shell
+    # Optional: add it in your ~/.bashrc or ~/.profile
+    source ~/esp/esp-idf/export.sh
+    ```
+
+    And finally compile and install your project.
+
+    ```sh
+    # Compile it
+    cd ~/src/my_project
+    idf.py build
+
+    # Flash + open debug terminal
+    idf.py flash monitor
+    ```
+
+[toolchain-deps]: https://docs.espressif.com/projects/esp-idf/en/latest/esp32/get-started/linux-setup.html
+[ttyusb0]: https://docs.espressif.com/projects/esp-idf/en/latest/esp32/get-started/establish-serial-connection.html#linux-dialout-group
+
+## Using 3rd party Arduino libraries
+
+To include 3rd party Arduino libraries in your project, you have to:
+
+* Add them to the `components` folder.
+* Add a file `component.mk` and/or `CMakeLists.txt` inside the component's folder
+
+`component.mk` is needed if you use `make` to compile it. And `CMakeLists.txt` is needed if you use `idf.py` to compile it.
+
+Let's use a real case as example:
+
+### Example: Adding ESP32Servo
+
+Suppose you want to use [ESP32Servo] project. The first thing to notice is that the source files are placed
+in the `src` folder.  We have to create a `component.mk` and/or `CMakeLists.txt` files that tells the
+ESP-IDF to look for the sources in the `src` folder.
+
+Example:
+
+```sh
+# 1) We clone ESP32Servo into components folder
+cd components
+git clone https://github.com/madhephaestus/ESP32Servo.git
+cd ESP32Servo
+```
+
+And now create create these files files inside `components/ESP32Servo` folder:
+
+```sh
+# 2) Create component.mk file
+# Only needed if you use "make" to compile the project
+# Copy & paste the following lines to the terminal:
+cat << EOF > component.mk
+COMPONENT_ADD_INCLUDEDIRS := src
+COMPONENT_SRCDIRS := src
+EOF
+```
+
+```sh
+# 3) Create CMakeLists.txt file
+# Only needed if you use "idf.py" to compile the project
+# Copy & paste the following lines to the terminal:
+cat << EOF > CMakeLists.txt
+idf_component_register(SRC_DIRS "src"
+                    INCLUDE_DIRS "src"
+                    REQUIRES "arduino")
+EOF
+```
+
+Finally, if you use `idf.py`, you have to update the dependencies in the `main/CMakeLists.txt`. E.g:
+
+```sh
+# Needed if you use "idf.py" to compile the project
+cd main
+edit CMakeLists.txt
+```
+
+...and append `ESP32Servo` to `REQUIRES`. The `main/CMakeLists.txt` should look like this:
+
+```cmake
+idf_component_register(SRCS "${srcs}"
+                    INCLUDE_DIRS "."
+                    REQUIRES "${requires}" "ESP32Servo")
+```
+
+And that's it. Now you can include `ESP32Servo` from your code. E.g:
+
+```cpp
+// Add this include in your arduino_main.cpp file
+#include <ESP32Servo.h>
+```
+
+[esp32servo]: https://github.com/madhephaestus/ESP32Servo.git
+
+## IDE
+
+Arduino IDE is not supported, but you can use [Visual Studio Code][vscode] + [ESP-IDF plugin][esp-idf-plugin].
+
+You can do:
+
+* All the regular Visual Studio Code regular features
+* ...plus configure, build, flash and monitor your project
+* ...and much more
+
+![ide](https://lh3.googleusercontent.com/pw/AM-JKLUxjqUhU2tM-bKw3togS3gTkBdtmi40kqW2c2KieAybnD770I3pdaLnFU7a-sM7dUUGmcWpigvElc1fGo1J-5bJlVdbg8HOJZKbUXo6A_IqIvUGEK6GtwxqNy5EFJmijrBnB_aQhd_fi3GQnXZ1V7WYvw=-no)
+
+Subjective opinion: VSCode + ESP-IDF plugin is muuuuuch better than Arduino IDE. Highly recommended!
+
+[vscode]: https://code.visualstudio.com/
+[esp-idf-plugin]: https://docs.espressif.com/projects/esp-idf/en/latest/esp32/get-started/vscode-setup.html
+
+
+
 ## Related Link
 
+This detailed compilation instruction comes from this awesome repository: [Bluepad32 for Arduino](https://gitlab.com/ricardoquesada/bluepad32/-/blob/main/docs/plat_arduino.md)
+
 - **Datasheet** 
    - [ESP32](https://m5stack.oss-cn-shenzhen.aliyuncs.com/resource/docs/datasheet/core/esp32_datasheet_en.pdf)
    - [SHT30 Datasheet](https://m5stack.oss-cn-shenzhen.aliyuncs.com/resource/docs/datasheet/unit/SHT3x_Datasheet_digital.pdf)

src/M5EPD_Driver.cpp

@@ -34,7 +34,7 @@ M5EPD_Driver::~M5EPD_Driver() {
 
 m5epd_err_t M5EPD_Driver::begin(int8_t sck, int8_t mosi, int8_t miso, int8_t cs,
                                 int8_t busy, int8_t rst) {
-    _epd_spi->begin(sck, miso, mosi, 4);
+    _epd_spi->begin(sck, miso, mosi, -1);
     _pin_cs   = cs;
     _pin_busy = busy;
     _pin_sck  = sck;