Discovery OS

A toy operating system.

Currently a bootloader is not included. Fortunatly QEMU provides a start mode where it will load a multiboot kernel.

Running the operating system

We run the operating system inside QEMU. On an Ubuntu system it can be installed like so:

apt-get install qemu

To run DiscoveryOS in QEMU without debugging:

make run

To run in QEMU with GDB:

make debug

Then press 'c' to continue execution, as QEMU/GDB will started in a paused state.

Notes

• Kernel image is loaded at 0x100000 (1M) and address range 1-4M is reserved for the kernel

References

• Multiboot specification
• GNU Linker documentation
• GNU Compiler inline assembly
  • Machine specific constraints
• Keyboard
  • PS/2 Keyboard - OSDev
  • Operating Systems Development - Keyboard
  • 8042 PS/2 Controller - OSDev
  • 8042 - Keyboard Controller (AT,PS/2)
• 8259A PIC
  • 8259A Programmable Interrupt Controller