Measurement Computing ADLIB WIN - Manual (Page 59)

Chapter 16 Logical Device Transfer Methods 15-1
15. LOGICAL DEVICE TRANSFER METHODS
Depending on the acquisition needs, the device may be controlled through a Software control routine
within the board’s driver or via DMA through the PC’s system hardware. Typically high-speed acquisition
modes require DMA and slower modes can use software routines.
15.1 AL_SetDataTransferMethod
Prototype C\C++
ERRNUM AL_SetDataTransferMethod(LHLD lhld, LPSTR lpstrMethod);
Visual Basic for Windows
Function AL_SetDataTransferMethod(ByVal lhld As Long,
ByVal lpstrMethod As String) As Long
LHLD lhld
handle of the LDSD
LPSTR lpstrMethod address of the transfer method string
The AL_SetDataTransferMethod function sets the hardware transfer operation method of the LDSD. See
section
4.2 OPERATING MODES for additional details.
Parameter Description
lhld Identifies the instance of the logical device subsystem.
lpstrMethod
Points to the desired transfer mode string. The available settings are defined
in the ADLIB include file as follows:
• AL_DTM_SOFTWARE software data transfers
• AL_DTM_DMA DMA data transfers
Returns:
On success ERRNUM is set to 1, otherwise ERRNUM contains the last error code that occurred during the
call.
Related Functions:
AL_GetDataTransferMethod
Program References:
Adlai01, Adlai02, Adlai04, Adlai05, Adlai07, Adlai08
Adlda01, Adlda02, Adlda03
Supported Logical Device Subsystems:
Pci55xx Series: CTR0, CTR1, CTR2, CTR3, Options:
SOFTWARE
Note that CTR0, CTR1 Counters are referenced in the user manual as CNTR0/1 and
Timers CTR2, CTR3 are referenced in the user manual as TMR0/1.
Pci55xx Series: DIN0 to DIN3, DOT0 to DOT3, Options: SOFTWARE
Pci55xx Series: ADC0, DAC0, DAC1, Options: SOFTWARE or DMA