portio.c File Reference

#include <ntddk.h>
#include "mpu401.h"

Include dependency graph for portio.c:

Go to the source code of this file.

Functions
BOOLEAN	WaitToSend (ULONG BasePort)
BOOLEAN	WaitToReceive (ULONG BasePort)
BOOLEAN	InitUARTMode (ULONG BasePort)

Function Documentation

InitUARTMode()

BOOLEAN InitUARTMode

(

ULONG

BasePort

)

Definition at line 64 of file portio.c.

{
    ULONG TimeOut;
    UCHAR Status = 0;
 
    DbgPrint("InitUARTMode() called\n");
 
    // Check if it's OK to send
    if (! WaitToSend(BasePort))
        return FALSE;
 
    DbgPrint("Resetting MPU401\n");
 
    // Send an MPU reset:
    MPU401_WRITE_COMMAND(BasePort, 0xff);
 
    // Check if it's OK to receive (some cards will ignore the above reset
    // command and so will not issue an ACK, so time out is NOT an error)
    DbgPrint("Waiting for an ACK\n");
    if (WaitToReceive(BasePort))
    {
        // Check to make sure the reset was acknowledged:
        for (TimeOut = MPU401_TIMEOUT;
             (Status = (MPU401_READ_DATA(BasePort) & 0xfe) && TimeOut > 0);
             TimeOut --);
    }
 
    DbgPrint("Entering UART mode\n");
    // Now we kick the MPU401 into UART ("dumb") mode
    MPU401_WRITE_COMMAND(BasePort, 0x3f);
 
    return TRUE;
}

Referenced by InitDevice().

WaitToReceive()

BOOLEAN WaitToReceive

(

ULONG

BasePort

)

Definition at line 40 of file portio.c.

{
    int TimeOut;
 
    DbgPrint("WaitToSend ");
 
    // Check if it's OK to receive
    for (TimeOut = MPU401_TIMEOUT;
         ! MPU401_READY_TO_RECEIVE(BasePort) && TimeOut > 0;
         TimeOut --);
 
    // If a time-out occurs, we report failure
    if (! TimeOut)
    {
        DbgPrint("FAILED\n");
        return FALSE;
    }
 
    DbgPrint("SUCCEEDED\n");
 
    return TRUE;
}

Referenced by InitSoundCard(), and InitUARTMode().

WaitToSend()

BOOLEAN WaitToSend

(

ULONG

BasePort

)

Definition at line 16 of file portio.c.

{
    int TimeOut;
 
    DbgPrint("WaitToSend ");
 
    // Check if it's OK to send
    for (TimeOut = MPU401_TIMEOUT;
         ! MPU401_READY_TO_SEND(BasePort) && TimeOut > 0;
         TimeOut --);
 
    // If a time-out occurs, we report failure
    if (! TimeOut)
    {
        DbgPrint("FAILED\n");
        return FALSE;
    }
 
    DbgPrint("SUCCEEDED\n");
 
    return TRUE;
}

Referenced by InitSoundCard(), and InitUARTMode().