boot/freeldr/freeldr/arch/i386/pc/pcbeep.c

   1 /*
   2  * PROJECT:     FreeLoader
   3  * LICENSE:     GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
   4  * PURPOSE:     Hardware-specific beep routine
   5  * COPYRIGHT:   Copyright 1998-2003 Brian Palmer (brianp@reactos.org)
   6  */
   7
   8 #include <freeldr.h>
   9
  10 #if defined(SARCH_XBOX)
  11 #define CLOCK_TICK_RATE 1125000
  12 #else
  13 #define CLOCK_TICK_RATE 1193182
  14 #endif
  15
  16 static VOID
  17 Sound(USHORT Frequency)
  18 {
  19     USHORT Scale;
  20
  21     if (Frequency == 0)
  22     {
  23         WRITE_PORT_UCHAR((PUCHAR)0x61, READ_PORT_UCHAR((PUCHAR)0x61) & ~3);
  24         return;
  25     }
  26
  27     Scale = CLOCK_TICK_RATE / Frequency;
  28     WRITE_PORT_UCHAR((PUCHAR)0x43, 0xB6);
  29     WRITE_PORT_UCHAR((PUCHAR)0x42, Scale & 0xFF);
  30     WRITE_PORT_UCHAR((PUCHAR)0x42, Scale >> 8);
  31     WRITE_PORT_UCHAR((PUCHAR)0x61, READ_PORT_UCHAR((PUCHAR)0x61) | 3);
  32 }
  33
  34 VOID PcBeep(VOID)
  35 {
  36     Sound(700);
  37     StallExecutionProcessor(100000);
  38     Sound(0);
  39 }