Improve existing README.md to cover more folders (projects)

.github/Doxyfile

@@ -1,5 +1,5 @@
 PROJECT_NAME           = "CH32V003 InspireMatrix"
-INPUT                  = data emulator i2c-comm movingnum paint-cursor paint-exe rv rv-dis testing tic-tac-toe README.md
+INPUT                  = data emulator ch32v003_stt eeprom i2c-comm inspire3d-demo movingnum movingcar paint paint-cursor rv-asm rv-dis save-rvasm savepaint snake-game testing tic-tac-toe README.md
 RECURSIVE              = YES
 USE_MDFILE_AS_MAINPAGE = README.md
 BUILTIN_STL_SUPPORT    = YES

README.md

@@ -1,37 +1,87 @@
 # InspireMatrix + CH32V003
 
-## Description
+This repository contains various projects and utilities for
+working with the CH32V003 microcontroller.
 
-Projects:
+Older hardware (InspireMatrix):
+![InspireMatrix](inspire_matrix.jpeg)
+
+## Project Structure
+
+* `.github`:
+  * `workflows`: GitHub Actions workflows.
+  * `Doxyfile`: Doxygen configuration.
+
+* `.vscode`:
+  * `settings.json`: VSCode settings:
+
+    ```json
+    "C_Cpp.default.compilerPath": "riscv-none-elf-gcc",
+    ```
+
+  To set the default compiler to `riscv-none-elf-gcc` for IDE integration.
 
 * `ch32v003_stt`
   * Simple spoken digit recognition.
   * Originally from <https://github.com/brian-smith-github/ch32v003_stt>
+  * Read its [README.md](ch32v003_stt/STT-README.md) for more information.
 
 * `ch32v003fun`
   * `driver.h`: Contains the most frequently used functions for the CH32V003.
-  * `i2c_events.h`: Contains some frequently used I2C functions.
-  * Originally from <https://github.com/cnlohr/ch32v003fun>
+  * `i2c_events.h`: Contains some frequently used I2C functions written manually.
+  * `i2c_tx.c`, `i2c_tx.h`, `oled_min.c`, `oled_min.h`: Contains some frequently used functions for the SSD1306 OLED display. Comes from <https://github.com/eric15342335/inspirelab-game>
+  * `ws2812b_simple.h`: Contains one function for controlling the WS2812B LEDs.
+  You need to declare the following variables in your code:
+  In `funconfig.h`:
+
+    ```c
+    #define FUNCONF_SYSTICK_USE_HCLK 1
+    ```
+
+    In your code (e.g. `main.c`):
+
+    ```c
+    #define WS2812BSIMPLE_IMPLEMENTATION
+    // ...
+    #include "ws2812b_simple.h"
+    ```
+
+  * Originally from the `extralibs` folder in <https://github.com/cnlohr/ch32v003fun>
 
 * `data`
   * `buttons.h`: Button ADC calibration data.
-  * `colors.h`: RGB color data for WS2812B LEDs.
+
+    Contains two sets of data, one for the first prototype
+    `InspireMatrix` and one for the second prototype `InspireComputer` (which uses two ADC channels for buttons). If you are using the `InspireComputer`, declare the following in `funconfig.h`:
+
+    ```c
+    #define INTERNAL_INSPIRE_MATRIX
+    ```
+
+  * `colors.h`: Contains the color palette for the `InspireMatrix` or `InspireComputer`.
+
+    One global variable `led_array[]` act as buffer to store the color data to be displayed.
+    Provides functions to manipulate the `led_array[]` buffer.
+
   * `fonts.h`: Display numbers and characters in the size of 3x5 on WS2812B LEDs.
+
   * `music.h`: Frequencies, durations and functions for playing music using a buzzer.
+  To play sound, use `JOY_sound()`.
 
 * `emulator`
   * Support development of basic embedded system software on Windows/MacOS without requiring
   physical hardware.
   * Aims to achieve function compatibility with the `ch32v003fun` library.
 
-* `i2c-comm` (Working in progress)
-  * Communication between two boards using I2C.
+* `i2c-comm`
+  * Communication between two boards using I2C protocol. The code contains a master and a slave.
 
 * `misc`
   * `libgcc.a` required by the `ch32v003fun` library on MacOS. See [here](misc/README.md) for more information.
 
 * `movingnum`
   * Animations of numbers moving from right to left, bottom to top. Uses math instead of hard coding.
+  Demonstrates the use of `fonts.h`.
 
 * `paint-cursor`
   * Draw images on `InspireMatrix` with direction buttons and matrix buttons
@@ -44,7 +94,7 @@ Projects:
 
 * `rv-asm`
   * Coding RISC-V Compressed instructions on a board with buttons, and showing the result on the matrix.
-  * Originally from <https://github.com/brian-smith-github/rv>
+  * Originally from <https://github.com/mnurzia/rv>
 
 * `rv-dis` (Working in progress)
   * Disassemble RISC-V compressed instructions and print the result on an external OLED display (e.g. SSD1306).
@@ -54,6 +104,15 @@ Projects:
   * This folder contains a bunch of test programs that are subject to change, and are not guaranteed to work for
   your specific hardware.
 
+* `savepaint`
+  * Todo
+
+* `save-rvasm`
+  * Todo
+
+* `snake-game`
+  * Porting the classic snake game to `InspireMatrix`, which has `8x8`=`64` LEDs and `up / down / left / right` controls.
+
 * `tic-tac-toe`
   * Play tic-tac-toe with a bot
   * Press button to start

data/colors.h

@@ -38,7 +38,7 @@ color_t color_divide(color_t color, uint8_t divider) {
 
 #define smaller(x, y) ((x) < (y) ? (x) : (y))
 void set_color(uint8_t led, color_t color) {
-    uint8_t divider = 8;
+    uint8_t divider = 1;
     led_array[led].r = smaller(color.r, color.r / divider);
     led_array[led].g = smaller(color.g, color.g / divider);
     led_array[led].b = smaller(color.b, color.b / divider);