functional floppy driver (in emulators at least)

1 files changed, 30 insertions, 0 deletions

diff --git a/README.md b/README.md
index 62a6560..0ee580e 100644
--- a/README.md
+++ b/README.md
@@ -38,6 +38,36 @@ Issues
 * redesign command handling (not inside the interrupt!!!)
 * implement a real shell (in user mode)
 
+
+MEMORY LAYOUT
+=============
+
+FLOPPY IMAGE
+------------
+0x0000 - MASTER BOOT RECORD
+0x0200 - kernel image (contains sotrage for interrupt desc. table)
+0x8000 - file system will go here
+
+RAM
+---
+0x1000
+    boot loader puts the kernel here.
+
+0x7c00 
+    first stage boot loader (loaded by bios) boot/mbr.asm
+    includes initial Global Descriptor Table!
+
+0x7c00 + 3
+    boot loader puts number of boot floppy disk here.
+
+0x7c00 + 0x140 
+    the boot loader puts the memory map obtained from the 
+    bios here before switching to protected mode.
+
+0xb000 
+    memory above this is used for dma (by our floppy.c driver)
+
+
 REFERENCES
 ==========