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#include "kernel.h" // general kernel config & includes
#include "console.h" // this will allow us to write to screen
// TODO: cleanup . how can i compile it without the includes!??
/// PIT /// Timer stuff
/*
http://www.brokenthorn.com/Resources/OSDevPit.html
vcc/gnd - voltage/ground
D0-D7 - data lines (data bus)
wr/rd - writing / reading (system control bus)
cs - ignore wr/rd or not (address bus)
a0-a1 (address bus)
// the three 16bit down counters/timers/channels
clk 0-2 (in)
gate 0-2 (in)
out 0-2 (out)
//typical
out1 -> pic interrupt on every tick (system timer)
out2 - was used for genearting dram memory refresh (Do not use)
out3 -> pc speaker
gate pins : depend on mode of operation
we do have modes 0-5.
*/
///////
void int_kb_handler();
////////// KERNEL MAIN///// /////
//
// test handler
void int_test_handler()
{
__asm__("pusha");
scr_put_string_nl("inside software interrupt handler 88");
__asm__("popa");
__asm__("leave");
__asm__("iret");
}
// clock handler
void int_clock_handler()
{
__asm__("pusha");
scr_put_string_nl(".");
// todo also the other pic!// TODO
__asm__("mov $0x20, %al");
__asm__("out %al, $0x20");
//
__asm__("popa");
__asm__("leave");
__asm__("iret");
__asm__("popa");
__asm__("leave");
__asm__("iret");
}
void kernel_main()
{
// clear console
scr_clear();
// hello message
scr_put_string_nl(KERNEL_HELLO_MESSAGE);
// init interrupt decriptor table
// install and enable!
int_init(0x08);
int_install();
// remember that we shifted all interrupts with the pic by 32
// so clock = 32 (irq 0)
// keyboard = 22 (irq 1)
// etc..
// install pit handler (programmable timer interrupt channel0)
int_install_ir(32, 0b10001110, 0x08,&int_clock_handler);
// install keyboard handler
int_install_ir(33, 0b10001110, 0x08,&int_kb_handler);
// install test handler
int_install_ir(88, 0b10001110, 0x08,&int_test_handler);
// now we can enable interrupts back again
int_enable();
scr_put_string_nl("Interrupts are up and running");
// kernel main loop
while(1)
{
}
}
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