Added sdk setup instructions

README.md

@@ -1,3 +1,122 @@
 # Nolibgs Hello Worlds !
 
-This repo is destined to host simple PsyQ hello worlds program for most basic stuff...
+So you want to begin developping on the original PSX but don't know where to start ?
+
+This repo is destined to host a bunch of simple examples, each describing how to do one thing.
+
+The code here will be using PsyQ, the "Official" Sony SDK, but we will not be using libGS, the Extended Graphics Library.
+
+Instead we'll try to devises methods to reproduce libgs functions. This will not necessarly more efficient, but we'll learn
+a lot more stuff !
+
+ 
+## Setting up the SDK : Modern GCC + PsyQ
+
+For this we'll rely heavily on grumpy-coder' s pcsx-redux, which will provide us with:
+
+  * A way to compile the code with a modern version of GCC
+  * An emulator with a lot of debugging features
+  
+### Let's do it !
+
+  * On windows, install WSL2 and Debian then launch a GNU/Linux terminal
+
+  1. Install the needed software packages ( aka dependencies in Linux world ) :
+
+```bash
+sudo apt-get install -y git make pkg-config clang-10 g++-9 gcc-mipsel-linux-gnu g++-mipsel-linux-gnu binutils-mipsel-linux-gnu libavcodec-dev libavformat-dev libavutil-dev libglfw3-dev libsdl2-dev libswresample-dev libuv1-dev zlib1g-dev
+```
+  
+  2. Clone the pcsx-redux repo : 
+  
+```bash
+git clone https://github.com/grumpycoders/pcsx-redux.git --recursive
+```
+  
+  3. Compile pcsx-redux : 
+  
+```bash 
+cd pcsx-redux && ./configure && make
+```
+  
+  4. Get the converted PsyQ 4.7 libs : 
+  
+```bash
+wget http://psx.arthus.net/sdk/Psy-Q/psyq-4.7-converted-full.7z
+```
+  
+  5. Extract to [...]pcsx-redux/src/mips/psyq/ : 
+
+```bash
+7z x -o/pcsx-redux/src/mips/psyq/
+```
+  
+  6. That's it ! After that you can check everything's working byt trying to compile some example code :
+  
+```bash 
+cd pcsx-redux/src/mips/psyq/
+make 
+```
+
+You should know have a 'cube.ps-exe' file in the folder. This a PSX executable you can load with most emulators.
+
+
+## Embedding binary data in a ps-exe
+
+So, if you don't know it yet, the fun in PSX development is to be able to upload your exes on real hardware with a USB/Serial cable.
+This means that the data you'll use in your program ( graphics, sounds, etc.) will have to be embedded in your exe in a binary form, 
+as you won't be able to stream them from the serial port. 
+
+/Well technically you could load them in memory before uploading your exe or stream them from a cd, but let's keep things simple for now./
+
+With our setup, this is quite easy !
+
+  1. In `pcsx-redux/src/mips/common.mk` , add the lines :
+  
+  ```mk
+# convert TIM file to bin
+%.o: %.tim
+	$(PREFIX)-objcopy -I binary --set-section-alignment .data=4 --rename-section .data=.rodata,alloc,load,readonly,data,contents -O elf32-tradlittlemips -B mips $< $@
+
+# convert VAG files to bin
+%.o: %.vag
+	$(PREFIX)-objcopy -I binary --set-section-alignment .data=4 --rename-section .data=.rodata,alloc,load,readonly,data,contents -O elf32-tradlittlemips -B mips $< $@
+```
+
+If you pay attention, you can see that's the same command, but for different file types. TIM files are bitmap images and VAG is the sound format used in this example.
+Each time you'll want to add a file type, just duplicate and change `%.vag` to `%.filetype`
+
+Then, in your project folder, copy the makefile from the cube example :
+
+```bash
+mkdir new_project && cd new_project
+cp ../cube/Makefile ../
+```
+
+All you have to do now is add the files you wish to embed to the SRCS variable, without forgetting the \ :
+
+```bash
+SRCS = main.c \
+../common/crt0/crt0.s \
+file_to_embed.ext \
+```
+
+  2. So this part takes care of converting our data to binary. Now to access them from your program, just use this in your sources :
+```c
+extern ulong _binary_filename_extension_start[]; 
+extern ulong _binary_filename_extension_end[];
+extern ulong _binary_bowsht_tim_length[];
+```
+
+The filename variable must begin with `_binary_` followed by the full path of your file, with . and / replaced by _ (underscore), and end with `_start[];` or `_end[];` or `_length[];` [source](https://discord.com/channels/642647820683444236/663664210525290507/780866265077383189)
+
+`_start` and `_end` are pointers, while `_length` is a constant.
+
+That's it! When you'll type `make` next time, it should convert your files to .o, then include them in your ps-exe.
+
+# Links and Doc
+
+  * [https://psx.arthus.net/starting.html](Getting started)
+  * [https://ps1.consoledev.net/](Ps1 dev links)
+  * [http://psxdev.net/](psxdev.net)
+  * [https://discord.com/invite/N2mmwp?utm_source=Discord%20Widget&utm_medium=Connect](psxdev Discord)