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/*
*
* modified from original freebios code
* by Steve M. Gehlbach <steve@kesa.com>
*
*/
#include <arch/io.h>
#include <string.h>
#include <pc80/vga.h>
#include <console/console.h>
void beep(int ms);
static char *vidmem; /* The video buffer, should be replaced by symbol in ldscript.ld */
int vga_line, vga_col;
#define VIDBUFFER 0xB8000;
static void memsetw(void *s, int c, unsigned int n)
{
int i;
u16 *ss = (u16 *) s;
for (i = 0; i < n; i++) {
ss[i] = ( u16 ) c;
}
}
static void vga_init(void)
{
// these are globals
vga_line = 0;
vga_col = 0;
vidmem = (unsigned char *) VIDBUFFER;
// mainboard or chip specific init routines
// also loads font
vga_hardware_fixup();
// set attributes, char for entire screen
// font should be previously loaded in
// device specific code (vga_hardware_fixup)
memsetw(vidmem, VGA_ATTR_CLR_WHT, 2*1024); //
}
static void vga_scroll(void)
{
int i;
memcpy(vidmem, vidmem + COLS * 2, (LINES - 1) * COLS * 2);
for (i = (LINES - 1) * COLS * 2; i < LINES * COLS * 2; i += 2)
vidmem[i] = ' ';
}
static void vga_tx_byte(unsigned char byte)
{
if (byte == '\n') {
vga_line++;
vga_col = 0;
} else if (byte == '\r') {
vga_col = 0;
} else if (byte == '\b') {
vga_col--;
} else if (byte == '\t') {
vga_col += 4;
} else if (byte == '\a') {
//beep
beep(500);
} else {
vidmem[((vga_col + (vga_line *COLS)) * 2)] = byte;
vidmem[((vga_col + (vga_line *COLS)) * 2) +1] = VGA_ATTR_CLR_WHT;
vga_col++;
}
if (vga_col < 0) {
vga_col = 0;
}
if (vga_col >= COLS) {
vga_line++;
vga_col = 0;
}
if (vga_line >= LINES) {
vga_scroll();
vga_line--;
}
// move the cursor
write_crtc((vga_col + (vga_line *COLS)) >> 8, CRTC_CURSOR_HI);
write_crtc((vga_col + (vga_line *COLS)) & 0x0ff, CRTC_CURSOR_LO);
}
struct console_driver {
.init = vga_init,
.tx_byte = vga_tx_byte,
};
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