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Diffstat (limited to 'README.Wyoos')
-rw-r--r-- | README.Wyoos | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/README.Wyoos b/README.Wyoos new file mode 100644 index 0000000..7bf4909 --- /dev/null +++ b/README.Wyoos @@ -0,0 +1,23 @@ +IDT interupt descriptor table + +GDT global descriptor table +- set up segments +- code segments, RX, never W +- data segments, RW, never X +- 16-bit compatibility on Intel, so quite a nightmare +- asm( LGDT ) needed +=> we do GTD all in assembly, not really readable! Ideal would be to + do as much as possible in C/C++ (even with some zero-overhead + C++17 crazyness maybe) and then call a pure assembly function with + a pointer to the GTD doing the 'LGDT' assembly operation + +types: +- have local typedefs for DWORD32 or uint32_t (as Windows and POSIX did + it) + +keyboard: +- 0x20 PIC +- asm( outb( port, byte)), outb function => better have ports knowing + their own bandwith. + SlowPort8, slowing down assembly code + |