diff options
Diffstat (limited to 'src/drivers/pc80/pc/i8254.c')
| -rw-r--r-- | src/drivers/pc80/pc/i8254.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/drivers/pc80/pc/i8254.c b/src/drivers/pc80/pc/i8254.c index 914c9aed9c..e83f00e00f 100644 --- a/src/drivers/pc80/pc/i8254.c +++ b/src/drivers/pc80/pc/i8254.c @@ -3,6 +3,7 @@ #include <arch/io.h> #include <commonlib/helpers.h> #include <cpu/x86/tsc.h> +#include <delay.h> #include <pc80/i8254.h> /* Initialize i8254 timers */ @@ -110,3 +111,24 @@ unsigned long tsc_freq_mhz(void) return timer_tsc; } #endif + +void beep(unsigned int frequency_hz, unsigned int duration_msec) +{ + unsigned int count = CLOCK_TICK_RATE / frequency_hz; + + /* Set command for counter 2, 2 byte write, mode 3 */ + outb(TIMER2_SEL | WORD_ACCESS | MODE3, TIMER_MODE_PORT); + + /* Select desired Hz */ + outb(count & 0xff, TIMER2_PORT); + outb((count >> 8) & 0xff, TIMER2_PORT); + + /* Switch on the speaker */ + outb(inb(PPC_PORTB) | (PPCB_T2GATE | PPCB_SPKR), PPC_PORTB); + + /* Block for specified milliseconds */ + mdelay(duration_msec); + + /* Switch off the speaker */ + outb(inb(PPC_PORTB) & ~(PPCB_T2GATE | PPCB_SPKR), PPC_PORTB); +} |