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Code: Select all

#include "io/io.h"
#include "misc/ops.h"
#include "misc/startup_test.h"

void kmain(void* mbd, unsigned int magic)
{
	if(magic != 0x2BADB002)
	{
		put_string("Invalid Magic Number. Maybe you should get a wizard next time!\n");
		k_hang();
	}

	clear_screen();
	k_startup_test();
	put_string("Hello People,\n\nThis is a test.\n\nSee if you can pass it.\n\nYou failed.\n\n");
}

Code: Select all

/* io.h AOS Willow */

#define IO_IO_H

#define WHITE_ON_BLACK 0x07
#define VIDRAM_START 0xB8000
#define VIDRAM_END 0xB8FA0

unsigned char *videoram = (unsigned char *) VIDRAM_START;
const char cursor = '_';

int row = 1;
int column = 1;

void reset_cursor()
{
	*videoram = 0x00; // Erase Cursor
	videoram++;
	*videoram = 0x00;
	row = 1;
	column = 1;
	update_videoram();
}

void update_videoram()
{
	int x = (row - 1) * 160; // Number of characters to skip for rows
	int y = (column - 1); // Number of characters to skip for columns
	videoram = VIDRAM_START + (x + y);
}

void move_cursor(int newrow, int newcolumn)
{
	row = newrow;
	column = newcolumn;
	update_videoram();
	*videoram = cursor; // Set cursor
}

void clear_screen()
{
	reset_cursor();
	for(videoram = VIDRAM_START; videoram < VIDRAM_END; videoram++)
	{
		*videoram = 0x0;
	}
	reset_cursor();
}

void put_char(char data) // Wrapper for put_coloured_char
{
	put_coloured_char(WHITE_ON_BLACK, data);
}

void put_coloured_char(char colour, char data)
{
	*videoram = 0x00; // Remove cursor
	void write_char()
	{
		*videoram = data;
		videoram++;
		*videoram = colour;
		column++;
		update_videoram();
		*videoram = cursor; // Set cursor
		videoram++;
		*videoram = colour;
		videoram--;
		if(column < 160) column++;
		else
		{	
			if(row < 25)
			{
				row++;
				column = 1;
			}

			else clear_screen();
		}

		update_videoram();
	}

	if(videoram <= VIDRAM_END) // Is cursor in bounds?
	{
		if(data == '\n')
		{
			// Newline
			if(row < 25) row++;
			else
			{
				clear_screen();
				return; // Screen has been cleared. No need to continue
			}
			column = 1;
			update_videoram();
		}

		else
		{
			write_char();
		}
	}
	else // Clear screen before printing
	{
		clear_screen();
		write_char();
	}
}


void put_string(const char *string) // Wrapper for put_coloured_string
{
	put_coloured_string(WHITE_ON_BLACK, string);
}

void put_coloured_string(char colour, const char *string)
{
	while(*string != 0)
	{
		put_coloured_char(colour, *string);
		string++;
	}
}