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/*
* Copyright (C) 2014 René Kijewski <rene.kijewski@fu-berlin.de>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @ingroup x86
* @{
*
* @file
* @brief Trivial functions to write to the videoram.
*
* @author René Kijewski <rene.kijewski@fu-berlin.de>
*
* @}
*/
#include "x86_videoram.h"
#define VIDEORAM ((char *) 0xB8000)
void videoram_putc(char c)
{
static unsigned pos = 0;
if (c == '\n') {
pos += 80;
}
else if (c == '\r') {
pos = (pos / 80) * 80;
}
else {
VIDEORAM[2 * pos + 0] = c;
VIDEORAM[2 * pos + 1] = (char) 0x9E; /* light blue bg, light yellow fg */
++pos;
}
if (pos >= 25 * 80) {
pos = 0;
}
}
void videoram_put(const char *s)
{
for (; *s; ++s) {
videoram_putc(*s);
}
}
void videoram_puts(const char *s)
{
videoram_put(s);
videoram_put("\r\n");
}
void videoram_put_hex(unsigned long v)
{
char s[2 + 2 * sizeof v + 1];
char *p = &s[sizeof s];
*--p = 0;
do {
char c = v % 16;
v /= 16;
*--p = c + (c < 10 ? '0' : 'A' - 10);
} while (v > 0);
*--p = 'x';
*--p = '0';
videoram_put(p);
}