1 files changed, 136 insertions, 0 deletions
diff --git a/private/ntos/nthals/halalpha/pcspeakr.c b/private/ntos/nthals/halalpha/pcspeakr.c
new file mode 100644
index 000000000..912a87b2a
--- /dev/null
+++ b/private/ntos/nthals/halalpha/pcspeakr.c
@@ -0,0 +1,136 @@
+/*++
+
+Copyright (c) 1992, 1993  Digital Equipment Corporation
+
+Module Name:
+
+    pcspeakr.c
+
+Abstract:
+
+    This module implements the HAL speaker "beep" routines for the
+    Alpha system that use the standard PC speaker driven by an interval
+    timer.
+
+Author:
+
+    Jeff McLeman (mcleman)  23-Jun-1992
+
+Environment:
+
+    Kernel mode
+
+Revision History:
+
+--*/
+
+#include "halp.h"
+#include "eisa.h"
+
+
+BOOLEAN
+HalMakeBeep(
+    IN ULONG Frequency
+    )
+
+/*++
+
+Routine Description:
+
+    This function sets the frequency of the speaker, causing it to sound a
+    tone.  The tone will sound until the speaker is explicitly turned off,
+    so the driver is responsible for controlling the duration of the tone.
+
+Arguments:
+
+    Frequency - Supplies the frequency of the desired tone.  A frequency of
+                0 means the speaker should be shut off.
+
+Return Value:
+
+    TRUE  - Operation was successful (frequency within range or zero).
+    FALSE - Operation was unsuccessful (frequency was out of range).
+            Current tone (if any) is unchanged.
+
+--*/
+
+{
+    KIRQL oldIrql;
+    NMI_STATUS NmiStatus;
+    PEISA_CONTROL controlBase;
+    TIMER_CONTROL timerControl;
+    ULONG newCount;
+
+    controlBase = HalpEisaControlBase;
+
+    //
+    // Raise the IRQL to dispatch level and acquire the beep spinlock.
+    //
+
+    KeAcquireSpinLock(&HalpBeepLock, &oldIrql);
+
+    //
+    // Stop the speaker.
+    //
+
+    *((PUCHAR) &NmiStatus) = READ_PORT_UCHAR(&controlBase->NmiStatus);
+
+    NmiStatus.SpeakerGate = 0;
+    NmiStatus.SpeakerData = 0;
+
+    WRITE_PORT_UCHAR(&controlBase->NmiStatus, *((PUCHAR) &NmiStatus));
+
+    if (Frequency == 0) {
+        KeReleaseSpinLock(&HalpBeepLock, oldIrql);
+        return(TRUE);
+    }
+
+    //
+    // Calculate the new counter value.
+    //
+
+    newCount = TIMER_CLOCK_IN / Frequency;
+
+    //
+    // The new count must be less than 16 bits in value.
+    //
+    
+    if (newCount >= 0x10000) {
+        KeReleaseSpinLock(&HalpBeepLock, oldIrql);
+        return(FALSE);
+    }
+
+    //
+    // Set the speaker timer to the correct mode.
+    //
+
+    timerControl.BcdMode = 0;
+    timerControl.Mode = TM_SQUARE_WAVE;
+    timerControl.SelectByte = SB_LSB_THEN_MSB;
+    timerControl.SelectCounter = SELECT_COUNTER_2;
+
+    WRITE_PORT_UCHAR(&controlBase->CommandMode1, *((PUCHAR) &timerControl));
+
+    //
+    // Set the speaker timer to the correct mode.
+    //
+
+    WRITE_PORT_UCHAR(&controlBase->SpeakerTone, (UCHAR)newCount);
+    WRITE_PORT_UCHAR(&controlBase->SpeakerTone, (UCHAR)(newCount >> 8));
+
+    //
+    // Start the speaker.
+    //
+
+    NmiStatus.SpeakerGate = 1;
+    NmiStatus.SpeakerData = 1;
+
+    WRITE_PORT_UCHAR(&controlBase->NmiStatus, *((PUCHAR) &NmiStatus));
+
+    //
+    // Release the beep spinlock and restore the IRQL.
+    //
+
+    KeReleaseSpinLock(&HalpBeepLock, oldIrql);
+    return(TRUE);
+}