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#ifndef BDA_H
#define BDA_H
#include "utils.h"
#define BIOS_DATA_AREA_SEGMENT 0x40
static inline uint32_t bda_get_dword(unsigned int offset) {
uint32_t __far *p = MK_FP(BIOS_DATA_AREA_SEGMENT, offset);
return *p;
}
static inline uint16_t bda_get_word(unsigned int offset) {
uint16_t __far *p = MK_FP(BIOS_DATA_AREA_SEGMENT, offset);
return *p;
}
static inline uint8_t bda_get_byte(unsigned int offset) {
uint8_t __far *p = MK_FP(BIOS_DATA_AREA_SEGMENT, offset);
return *p;
}
#define bda_get_ebda_segment() bda_get_word(0x0e)
#define bda_get_video_mode() bda_get_byte(0x49)
#define bda_get_num_columns() bda_get_word(0x4a)
#define bda_get_video_page_size() bda_get_word(0x4c)
#define bda_get_cur_video_page() bda_get_word(0x62)
#define bda_get_last_row() bda_get_byte(0x84)
#define bda_get_char_height() bda_get_word(0x85)
#define bda_get_tick_count() bda_get_dword(0x6c)
#define bda_get_tick_count_lo() bda_get_word(0x6c)
static inline void bda_wait_tick() {
uint16_t cur_ticks = bda_get_tick_count_lo();
do {
pause();
} while (cur_ticks == bda_get_tick_count_lo());
}
static inline void bda_wait_ticks(unsigned int ticks) {
for (; ticks > 0; ticks--) {
bda_wait_tick();
}
}
#endif // BDA_H
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