Get loadf variables from the disk description table instead of hardcoding them, tidy up the make script a bit, add contributors to the copyright statement, and change the phrasing of the readme slightly.

LICENSE.MD

@@ -1,7 +1,7 @@
 MIT License
 ===========
 
-Copyright (c) 2021 CrazyEttin
+Copyright (c) 2021 CrazyEttin and contributors
 
 Permission is hereby granted, free of charge, to any person obtaining a
 copy of this software and associated documentation files (the

README.MD

@@ -2,8 +2,8 @@ EttinOS
 =======
 
 EttinOS is a minimalist 16-bit DOS-like hobbyist operating system for
-the IBM PC and compatible computers. Its git repository can be found at
+the IBM Personal Computer and compatible machines. Its git repository
-https://ahti.space/git/crazyettin/EttinOS.
+can be found at https://ahti.space/git/crazyettin/EttinOS.
 
 System requirements
 -------------------

make.sh

@@ -1,10 +1,7 @@
 #!/bin/sh
 
 rm -f EttinOS.img
-if [ ! -d "bin" ]
+mkdir -p bin
-then
-    mkdir bin
-fi
 
 cd src/
 if [ "$1" = "-1440" ]
@@ -16,13 +13,13 @@ nasm HELLO.ASM -f bin -o ../bin/HELLO.BIN
 
 cd ..
 if [ "$1" = "-1440" ]
-    then mkfs.fat -C EttinOS.img 1440
+    then mkfs.fat -C EttinOS.img 1440 1>/dev/null
-    else mkfs.fat -C EttinOS.img 360
+    else mkfs.fat -C EttinOS.img 360 1>/dev/null
 fi
 
 if which rw > /dev/null 2>&1
     then rw -i bin/BOOT.BIN -o EttinOS.img -b 512 -c 1x
-    else dd if=bin/BOOT.BIN of=EttinOS.img conv=notrunc bs=512 count=1
+    else dd if=bin/BOOT.BIN of=EttinOS.img conv=notrunc bs=512 count=1 1>/dev/null
 fi
 mcopy -i EttinOS.img bin/SYSTEM.BIN ::
 mcopy -i EttinOS.img bin/HELLO.BIN ::

src/BOOT.ASM

@@ -63,7 +63,7 @@ cli
 mov sp, 0x0
 sti
 ;Store the boot drive number
-mov [bootdrive], dl
+mov [drive], dl
 
 ;Load the root
 ;Set the source
@@ -202,11 +202,13 @@ boot:
 ;Clear
 pop cx
 pop bx
+;Pass the drive number to the system
+mov dl, byte [drive]
 ;Boot
 jmp 0x0:0x500
 
 ;Data
-bootdrive  db 0x0
+drive    db 0x0
 sysfile  db "SYSTEM  BIN"
 errormsg db "System not found", 0xd, 0xa, 0x0
 cluster  dw 0x0
@@ -230,7 +232,7 @@ mov dh, dl
 mov ch, al
 pop bx
 pop ax
-mov dl, byte [bootdrive]
+mov dl, byte [drive]
 ret
 
 ;Pad the binary to a full sector and make the disk bootable

src/LOADF.INC

@@ -67,6 +67,39 @@ jmp .done
 .load:
 pop ax
 
+;Load the disk description table
+;Set the source
+mov dl, [drive]
+mov ch, 0x0
+mov dh, 0x0
+mov cl, 0x1
+;Set the destination
+mov si, buffer
+mov bx, si
+;Set the size
+mov al, 0x1
+;Load
+mov ah, 0x2
+int 0x13
+
+;Store the disk values used for the rest of the call
+mov ax, word [buffer + 0xb]
+mov word [.sectorsize], ax
+mov al, byte [buffer + 0xd]
+mov byte [.clustersize], al
+mov ax, word [buffer + 0xe]
+mov word [.bootsectors], ax
+mov al, byte [buffer + 0x10]
+mov byte [.fats], al
+mov ax, word [buffer + 0x11]
+mov word [.rootentries], ax
+mov ax, word [buffer + 0x16]
+mov word [.sectorsperfat], ax
+mov ax, word [buffer + 0x18]
+mov word [.sectorspertrack], ax
+mov ax, word [buffer + 0x1a]
+mov word [.sides], ax
+
 ;Load the root
 ;Set the source
 mov ah, 0x0
@@ -219,21 +252,18 @@ mov al, 0x1
 iret
 
 ;Data
-.file     times 0xb db 0x20
+.sectorsize      dw 0x0 ;bytes
-.errormsg db "File not found", 0x0
+.clustersize     db 0x0 ;sectors
-.cluster  dw 0x0
+.bootsectors     dw 0x0
-.pointer  dw 0x0
+.fats            db 0x0
-
+.rootentries     dw 0x0
-;These are temporary until i write something to load them from the disk itself
+.sectorsperfat   dw 0x0
-.bootdrive       db 0x0
+.sectorspertrack dw 0x0
-.sectorsize      dw 0x200 ;bytes
+.sides           dw 0x0
-.clustersize     db 0x2 ;sectors
+.file            times 0xb db 0x20
-.bootsectors     dw 0x1
+.errormsg        db "File not found", 0x0
-.fats            db 0x2
+.cluster         dw 0x0
-.rootentries     dw 0x70
+.pointer         dw 0x0
-.sectorsperfat   dw 0x2
-.sectorspertrack dw 0x9
-.sides           dw 0x2
 
 ;Check the file name and convert to upper case
 .checkconv:
@@ -278,7 +308,7 @@ sub al, 0x20
 .storech:
 ;Store the character
 stosb
-;Increase the counter
+;Decrease the counter
 dec bl
 ret
 
@@ -300,5 +330,5 @@ mov dh, dl
 mov ch, al
 pop bx
 pop ax
-mov dl, byte [.bootdrive]
+mov dl, byte [drive]
 ret

src/SYSTEM.ASM

@@ -50,6 +50,9 @@ mov [0x82], ax
 mov [0x86], ax
 mov [0x8a], ax
 
+;Store the boot drive number
+mov [drive], dl
+
 ;Print a welcome message
 mov si, welcomemsg
 mov ah, 0x2
@@ -102,6 +105,7 @@ int 0x21
 jmp shell
 
 ;Data
+drive      db 0x0
 welcomemsg db 0xd, 0xa, "Welcome to EttinOS!", 0xd, 0xa, 0x0
 prompt     db "> ", 0x0
 errormsg   db "Unknown command", 0x0