From 8fb0c27ac52a76dd27a5879bebb643f56abe348a Mon Sep 17 00:00:00 2001 From: Andreas Baumann Date: Sat, 29 Apr 2017 16:21:41 +0200 Subject: some documentation --- README | 4 ++++ src/README | 7 +++++++ src/switch_mode.asm | 3 ++- 3 files changed, 13 insertions(+), 1 deletion(-) create mode 100644 src/README diff --git a/README b/README index 8f082d8..0d29dbd 100644 --- a/README +++ b/README @@ -40,6 +40,10 @@ Next at t=14040244 links ----- +Writing a Simple Operating System - from Scratch, Nick Blundell +http://www.cs.bham.ac.uk/~exr/lectures/opsys/10_11/lectures/os-dev.pdf + +OS Development: Low-level Boot-Sector Programming, Nick Blundell https://www.youtube.com/watch?v=YvZhgRO7hL4&list=UUjrLiYrvbpXR37c0HV4PmqA http://www.intel.com/content/www/us/en/architecture-and-technology/64-ia-32-architectures-software-developer-manual-325462.html diff --git a/src/README b/src/README new file mode 100644 index 0000000..56ec7b2 --- /dev/null +++ b/src/README @@ -0,0 +1,7 @@ +boot.asm - the main boot sector code using: +* gdt.asm - the early GDT +* stage1_functions.asm - real mode functions of the bootloader +* stage2_functions.asm - protected mode primitive VGA routines +* switch_mode.asm - early GTD loading and switching from real to protected mode +kernel.c - Kernel C entry point 'entry' + diff --git a/src/switch_mode.asm b/src/switch_mode.asm index 32cca0b..bc38b5a 100644 --- a/src/switch_mode.asm +++ b/src/switch_mode.asm @@ -3,7 +3,8 @@ %include "gdt.asm" switch_to_protected_mode: - ; switch off interrupts for now + ; switch off interrupts for now, we don't + ; have a valid IDT installed yet cli ; load GDT (global descriptor table) -- cgit v1.2.3-54-g00ecf