A DMA checkbox that won't stay checked when you restart the system is a good indication that your computer does not support DMA properly. Unfortunately, this method of determining support is not foolproof. DMA may appear to install successfully, but may have intermittent problems anyway. Any of the following symptoms may or may not indicate a DMA problem:.
If any of these problems occur, it does not necessarily mean that you cannot use DMA with your computer. The following are likely causes of the problems:. According to the ATA standard, cables can be no longer than 18" 0.
These long cables may not work reliably, if at all, with high-speed DMA modes. Cables also vary greatly in quality. When you're installing a hard drive, always replace the old ATA cable with the cable that comes with the drive. If no cable came with the drive, buy a good-quality DMA cable separately. Bursts must not be used if the total length as given by nMinus1 is less than the arbitration rate configured for the descriptors.
Notice that this setting is used for both the primary and alternate descriptors. This parameter determines if bursts should be enabled during DMA transfers using the alternate descriptors. Bursts must not be used if the total length as given by nMinus1 for the alternate descriptor is less than the arbitration rate configured for the descriptor.
The last descriptor will have its cycle control type reprogrammed to basic type. Maximum number of alternate descriptors is Configure a DMA channel. Note If using this function on a channel already in use by the DMA controller, the behaviour is undefined. Parameters [in] channel DMA channel to configure.
Note If using this function on a descriptor already activated and in use by the DMA controller, the behaviour is undefined. Parameters [in] channel DMA channel to configure for. Parameters [in] descr Points to start of memory area holding the alternate descriptors. Configure DMA channel 2D transfer properties. Enable or disable a DMA channel. Parameters [in] channel DMA channel to enable or disable. If 'false' the channel will be disabled. Check if DMA channel is enabled.
Parameters [in] channel DMA channel to check. Returns true if channel is enabled, false if not. Enable or disable a DMA channel request. Parameters [in] channel DMA channel to enable or disable request on. If 'false' request will be disabled. Initializes DMA controller. Note Must be invoked before using the DMA controller. Parameters [in] init Pointer to a structure containing DMA init information.
Clear one or more pending DMA interrupts. Parameters [in] flags Pending DMA interrupt sources to clear. Disable one or more DMA interrupts. Parameters [in] flags DMA interrupt sources to disable. Enable one or more DMA interrupts. Note Depending on the use, a pending interrupt may already be set prior to enabling the interrupt. Parameters [in] flags DMA interrupt sources to enable. Get pending DMA interrupt flags.
Note The event bits are not cleared by the use of this function. Returns DMA interrupt sources pending. Note Interrupt flags are not cleared by the use of this function. Set one or more pending DMA interrupts. Parameters [in] flags DMA interrupt sources to set to pending.
Interrupt handler for DMA cycle completion handling. The kernel debugger extension! It can display various details about the behavior of each DMA adapter.
There is a detailed example of the! See Windows Debugging for details. For details, see Selecting Driver Verifier Options. To activate DMA Verification, use a flag value of 0x80 or add 0x80 to the flag value.
For example:. This setting is effective immediately, but is lost when you shut down or reboot the computer. For details, see Using Volatile Settings.
The DMA Verification feature is also included in the standard settings. Skip to main content. This browser is no longer supported.
Download Microsoft Edge More info. Contents Exit focus mode.
0コメント