ad_ch_no : A/D channel number

ad_range : A/D analog input range, the possible values are shown in section 4.3.8.

count : the number of A/D conversion

ad_buffer(DOS) :the start address of the memory buffer to store the AD data, the buffer size must large than the number of AD conversion.

In DOS environment, please make sure this memory is double-word alignment. Every 16-bit unsigned integer data in ad_buffer:

D11 D10 D9 .......................

D1 D0

C3 C2

C1 C0

D11, D10, ..., D1, D0 : A/D converted data

 

C3, C2, C1, C0

: converted channel no.

memID(Windows-95) :the memory ID of the allocated system DMA

memory. In Windows 95 environment, before calling W_9112_AD_DMA_Start, W_9112_Alloc_DMA_Mem must be called to allocate a contiguous DMA memory. W_9112_Alloc_DMA_Mem will return a memory ID for identify the allocated DMA memory, as well as the linear address of the DMA memory for user to access the data. The format of the A/D data is the same as DOS buffer (ad_buffer argument). c1 : the 16-bit timer frequency divider of timer channel #1

c2 : the 16-bit timer frequency divider of timer channel #2

uReturn Code

ERR_NoError, ERR_BoardNoInit, ERR_InvalidADChannel, ERR_AD_InvalidRange, ERR_InvalidTimerValue

uExample

See Demo Program 'AD_DEMO3.C' , 'AD_DEMO6.C'

5.15 _9112_AD_DMA_Status

uDescription

Since the _9112_AD_DMA_Start function executs in background, you can issue the function _9112_AD_DMA_Status to check its operation status.

uSyntax

Visual C++ (Windows-95)

int W_9112_AD_DMA_Status (int card_number, int *status, int * count)

Visual Basic (Windows-95)

W_9112_AD_Status (ByVal card_number As Long, status As Long, count As Long) As Long

C/C++ Library ∙ 53