Added some docs and improved editor

README.md

@@ -1,6 +1,36 @@
 # kern.
+---
 
-This is a second version of Kern. 
+Idk why i called it that it was 3am and i needed sleep
-I am making this because idk how to make a filesystem in the original Kern.
 
-At some point i will probably make this repo Kern and the other one like an archive or something Idk
+## About
+Kern is a 32-bit OS based on the x86 architecture written in NASM Assembly and C. 
+
+It supports a basic command line and has a custom filesystem.
+
+_Note: The filesystem is currently a basic filetable._
+
+## Usage
+If you want to try kern for some reason, you can.
+You might be able to find some releases, or build it using the build.sh script.
+
+For building, you'll need these tools:
+- [NASM](https://www.nasm.us/)
+- [QEMU](https://www.qemu.org/) (for emulation)
+
+I personally wouldn't recommend running this on real hardware, because it's untested and will just probably break you pc, but if you really want to, you can try it, but don't blame me if something goes wrong.
+
+If you don't know how to do something, try the 'help' command!
+
+## Some images
+
+The command prompt: \
+![CLI image](other/example.png)
+
+Built-in code editor: \
+![Code Editor](other/editor.png)
+
+Graphics mode test: \
+![Graphics Test](other/graphics.png)
+
+_These images may be outdated, Idk_

src/boot.asm

@@ -59,6 +59,11 @@ start:
     mov es, ax
     mov fs, ax
     mov gs, ax
+
+    ; Setup stack
+    mov bp, 0xffff
+    mov sp, bp
+    mov ax, 0x9000
     mov ss, ax
 
     mov bl, byte [driveNumber]

src/fs/calc.asm

@@ -13,7 +13,6 @@ start:
     mov es, ax
     mov fs, ax
     mov gs, ax
-    mov ss, ax
 
     jmp 0x2000:0x0000
 

src/fs/edit.asm

@@ -1,9 +1,16 @@
 [bits 16]
 
 launch:
+    pusha
     call resetTextMode
-    mov si, headerMsg
+
-    call print
+    mov di, 0x0e60      ; Offset in vidmem (2nd to last line)
+    mov si, statusBarMsg
+    call drawString
+    mov di, 0x0f00      ; Last line
+    mov si, controlsMsg
+    call drawString
+
     xor cx, cx
     mov di, hexCode
 
@@ -34,10 +41,9 @@ getHexCh:
     rol byte [hexByte], 4
     or byte [hexByte], al
     mov al, [hexByte]
-    mov [di], al
+    stosb
     mov dx, [hexByte]
     call printHexByte
-    inc di
     xor cx, cx
     mov al, ' '
     mov ah, 0x0e
@@ -54,9 +60,14 @@ getHexCh:
     call print
     jmp getHexCh
 .runInput:
-    mov si, runMsg
+    pusha
+    call hexCode       ; Call the code
+    popa
+
+    mov si, ranMsg
     call print
-    call hexBegin       ; Call the code
+    xor ax, ax
+    int 0x16
     jmp launch
 
 ; Expects al to contain an ASCII character, will set bx to it's hex equivalent
@@ -69,13 +80,24 @@ asciiToHex:
     ret
 
 return:
+    mov cx, 256
+    mov di, hexCode
+.loop:
+    mov byte [di], 0
+    inc di
+    dec cx
+    jnz .loop
+
+    popa
+
     mov ax, 0x2000
+    mov es, bx
+    xor bx, bx
+
     mov ds, ax
     mov es, ax
     mov fs, ax
     mov gs, ax
-    mov ss, ax
-
     jmp 0x2000:0x0000
 
 ; - Includes -
@@ -83,19 +105,15 @@ return:
 %include "./src/lib/print.asm"
 ; ------------
 
-headerMsg: db   " - EDITOR - ", ENDL, \
+statusBarMsg: db " -- HEX -- ", 0
-                "Type '$' to run your code or '!' to exit", ENDL, ENDL, 0
+controlsMsg: db "'$' to execute code; '!' to quit", 0
-runMsg: db ENDL, " -- Executing -- ", ENDL, ENDL, 0
+ranMsg: db ENDL, ENDL, " - Finished Execution - ", ENDL, 0
 
-backChars: db 8, 8, 8, '  ', 8, 8, 0
+backChars: db 8,8,8,'  ',8,8,0
 
 hexByte: db 0
 
-hexBegin: ; The label we jump to
+hexCode: times 256 db 0     ; Code buffer
-    pusha
-hexCode: times 256 db 0     ; Code buffer (user input code)
-hexEnd: 
-    popa
     ret
 
 times 2*512-($-$$) db 0

src/kernel.asm

@@ -182,7 +182,6 @@ foundProgram:
     mov es, ax
     mov fs, ax
     mov gs, ax
-    mov ss, ax
 
     jmp PROGRAM_LOC:0x0000
 .printText:
@@ -385,7 +384,7 @@ driveNumber: db 0
 startMsg: db "kern.", ENDL, ENDL, 0 ; The bootup message
 prompt: db "> ", 0 ; Prompt for input
 fileNotFoundMsg: db "File not found!", ENDL, 0 ; User tries to load nonexistent file
-programLoadFailMsg: db "Failed while loading program!", ENDL, 0 ; File load fail
+programLoadFailMsg: db "Couldn't load file!", ENDL, 0 ; File load fail
 sectorLenText: db "512B", 0
 kilobyteText: db "kB", 0
 oneHalfText: db ".5kB", 0
@@ -394,16 +393,16 @@ fileListMsg: db " Filename      E# St   Size ", ENDL, \
                 "----------    ------- ------", ENDL, 0
 
 helpMsg: db "Available Commands:", ENDL, \
-            "clear - Clears the screen", ENDL, \
+            " clear  | Clears the screen", ENDL, \
-            "gfx - Graphics mode test", ENDL, \
+            " edit   | Opens the code editor", ENDL, \
-            "help - Prints this message", ENDL, \
+            " gfx    | Graphics mode test", ENDL, \
-            "ls - List all files", ENDL, \
+            " help   | Prints this message", ENDL, \
-            "reboot - Reboots the system", ENDL, 0
+            " ls     | List all files", ENDL, \
+            " reboot | Reboots the system", ENDL, ENDL, 0
 
 ; Commands
 ; TODO: Put these into a file or something
 clearCmd: db "clear", 0
-editCmd: db "edit", 0
 gfxCmd: db "gfx", 0
 helpCmd: db "help", 0
 lsCmd: db "ls", 0

src/lib/print.asm

@@ -5,7 +5,7 @@
 print:
     pusha
     mov ah, 0x0e
-    mov bl, 0x0f
+    mov bl, 0x1f
     mov bh, 0
 .loop:
     lodsb           ; Load [si] into al; Increment si
@@ -53,6 +53,8 @@ printHex:
 printHexByte:
     pusha
     xor cx, cx
+    mov bh, 0
+    mov bl, 0x1f    ; White on blue
 .loop:
     mov al, dl
     and al, 0xF0
@@ -84,6 +86,29 @@ clear:
     popa
     ret
 
+;
+; Writes a string into video memory
+; di - Video memory offset
+; si - string
+;
+drawString:
+    pusha
+    push es         ; For some reason doesn't get stored in pusha
+    mov ax, VIDMEM
+    mov es, ax
+.loop:
+    cmp byte [si], 0
+    je .after
+    movsb
+    mov byte [es:di], 0x1f  ; White on blue
+    inc di
+    jmp .loop
+.after:
+    pop es
+    popa
+    ret
+
 ; Usefull definitions
 %define ENDL 0x0a, 0x0d
+VIDMEM equ 0x0b800
 newline: db ENDL, 0 ; CRLF

test/test

@@ -1 +0,0 @@
-¸AÍ1ÀÍÃ

test/test.asm

@@ -1,5 +0,0 @@
-mov ax, 0x0e41
-int 0x10
-xor ax, ax
-int 0x16
-ret