void WaitDisplayReady(void)
// reads the display status byte and checks
// that the display is ready before writing

// doesn't have any check in case the status byte
// can't be read so this situation may cause a lockup

{

  int Tmp;

       Tmp = DlPortReadPortUshort(BASE + 0x402);
       Tmp = Tmp & 0x1F;
       Tmp = Tmp | 0x20;
       DlPortWritePortUshort(BASE + 0x402, Tmp);

       do{
             DlPortWritePortUshort(BASE + 2, 0x20 + 4 + 2);     //In, CD=1, CS=0, Wr=1
             DlPortWritePortUshort(BASE + 2, 0x20 + 4 + 2 + 8); //In, CD=1, CS=0, Wr=1, Rd=0
             Tmp = DlPortReadPortUshort(BASE);
             DlPortWritePortUshort(BASE + 2, 0x20 + 4 + 2);     //In, CD=1, CS=0, Wr=1

       }while ((Tmp & 3) != 3 );
       DlPortWritePortUshort(BASE + 2, 0);
   
}

while ((Tmp & 3) != 3 );

Public Sub WaitDisplayReady()
Dim lngTmp As Long
Dim lngDiff As Long

lngTmp = GetTickCount()
Do Until lngDiff > 2
    lngDiff = GetTickCount() - lngTmp
    DoEvents
Loop

End Sub

Do
    Call DlPortWritePortUshort(intBase + 2, 39)    '0x20 | CDHI | WRHI | RDLO | CELO
     intTmp = DlPortReadPortUshort(intBase)
    Call DlPortWritePortUshort(intBase + 2, 32) '0x20 + CEHI
Loop While (intTmp And 3) <> 3
Call DlPortWritePortUshort(intBase + 2, 0)
End Sub

 

    Public Sub WaitDisplayReady()
        Dim shtTemp As Short

        shtTemp = DlPortReadPortUshort(BASE_DADES + &H402)
        shtTemp = shtTemp And &H1F
        shtTemp = shtTemp Or &H20
        DlPortWritePortUshort(BASE_DADES + &H402, shtTemp)

        Do
            DlPortWritePortUshort(BASE_DADES + 2, &H20 + 4 + 2)     
            DlPortWritePortUshort(BASE_DADES + 2, &H20 + 4 + 2 + 8) 
            shtTemp = DlPortReadPortUshort(BASE_DADES)
            DlPortWritePortUshort(BASE_DADES + 2, &H20 + 4 + 2)     
        Loop While ((shtTemp And 3) <> 3)
        DlPortWritePortUshort(BASE_DADES + 2, 0)
    End Sub