Mercurial > lcfOS
view cos/kernel/video.c @ 180:25a0753da4cf
Re-organized files
author | Windel Bouwman |
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date | Thu, 09 May 2013 17:35:19 +0200 |
parents | d8627924d40d |
children |
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#include "kernel.h" #define VIDMEM 0xB8000 #define NUM_COLS 80 #define NUM_ROWS 25 #define SCREEN_SIZE (NUM_COLS * NUM_ROWS) static int row, col; uint8_t video_color = 0x1F; void move_cursor() { uint16_t cursorLocation = row * 80 + col; outb(0x3D4, 14); outb(0x3D5, cursorLocation >> 8); outb(0x3D4, 15); outb(0x3D5, cursorLocation & 0xFF); } void set_cursor(int newrow, int newcol) { row = newrow; col = newcol; move_cursor(); } void get_cursor(int *therow, int *thecol) { *therow = row; *thecol = col; } void set_color(int forecolor, int backcolor) { video_color = forecolor | (backcolor << 4); } void clear_screen() { unsigned char *vidmem = (unsigned char *) VIDMEM; int loop; for (loop = 0; loop < SCREEN_SIZE; loop++) { *vidmem++ = 0x20; *vidmem++ = video_color; } } void init_screen() { clear_screen(); set_cursor(0, 0); } static void scroll_screen() { uint8_t* v; int i; // Shift all lines one up: v = (uint8_t*)VIDMEM; for (i = 0; i < SCREEN_SIZE; i++ ) { *v = *(v + NUM_COLS*2); ++v; *v = *(v + NUM_COLS*2); ++v; } // Clear new line: v = (uint8_t*)VIDMEM + SCREEN_SIZE * 2 - NUM_COLS * 2; for (i = 0; i < NUM_COLS; i++) { *v++ = ' '; *v++ = video_color; } } static void new_line() { ++row; col = 0; if (row == NUM_ROWS) { scroll_screen(); row = NUM_ROWS - 1; } } static void clear_to_EOL() { int loop; unsigned char *v = (unsigned char *) ((uint64_t)(VIDMEM + row * NUM_COLS * 2 + col * 2)); for (loop = col; loop < NUM_COLS; loop++) { *v++ = ' '; *v++ = video_color; } } static void print_char(int c) { unsigned char *v = (unsigned char *) ((uint64_t)(VIDMEM + row * NUM_COLS * 2 + col * 2)); switch(c) { case '\n': clear_to_EOL(); new_line(); break; default: *v++ = (unsigned char) c; *v = video_color; if (col < NUM_COLS - 1) ++col; else new_line(); } move_cursor(); } void print_string(const char *s) { while (*s != '\0') { print_char(*s++); } }