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Move all documentation to README.adoc

Browse Source 
This includes both separate .md files, and documentation that was on the
head of the .S source files.

Retest everything as this was done, and fix a few easy things.
This commit is contained in:
Ciro Santilli
2018-05-06 14:33:33 +01:00
parent ce9636f324
commit fb3c7e04c4
110 changed files with 2945 additions and 3287 deletions
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35
bios_detect_memory.S
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@@ -1,38 +1,3 @@
/*
# Detecte memory
# int 15
TODO Seems to be outputting trash :-)
http://wiki.osdev.org/Detecting_Memory_%28x86%29
Determine how much memory you've got, and how much of it is low memory.
This is important in particular so that you can start your stack there
when you enter protected mode, since the stack grows down.
In 16-bit mode, it does not matter much,
since most modern machines have all addressable memory there,
but in 32-bit protected it does, as our emulator usually does not have all 4Gb.
And of course, 64-bit RAM is currently larger than the total RAM in the world.
`int 15` returns a list:
each time you call it a new memory region is returned.
The format is not too complicated, and documented at:
http://wiki.osdev.org/Detecting_Memory_%28x86%29#Detecting_Upper_Memory
- 8 bytes: base address of region.
- 8 bytes: length of region.
- 4 bytes: type or region. 1 for usable RAM.
- 4 bytes: some ACPI stuff that no one uses?
## Low memory
TODO what is it?
*/
#include "common.h"
BEGIN
CLEAR