User`s guide

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C/C++ Library
5.15 _8216_AD_DMA_Start
@ Description
The function will perform A/D conversion N times with DMA data
transfer by using the pacer trigger ( internal timer trigger). It will takes
place in the background which will not stop until the N-th conversion
has completed or your program execute _8216_AD_DMA_Stop()
function to stop the process. After executing this function, it is
necessary to check the status of the operation by using the function
_8216_AD_DMA_Status(). The function is performed on single A/D
channel with fixed gain. The sampling rate is 2 MHz/(c1xc2).
@ Syntax
int _8216_DMA_Start( int ad_ch_no, int ad_range,
intdma_ch_no, int irq_ch_no
int count , int *ad_buffer
unsigned int c1, unsigned int c2)
@ Argument
ad_ch_no:
A/D channel number
ad_gain:
A/D range value
Input Range (V) Gain Range Code
±10 V
X 1 0
±5 V
X 2 1
±2.5 V
X 4 2
±1.25 V
X 8 3
dma_ch_no:
DMA channel number, DMA_CH_1 or
DMA_CH_3. This should be the same as
the setting of JP8 and JP9 on hardware.
irq_ch_no:
IRQ channel number, used to stop DMA.
This should be the same as the setting
of JP7 on hardware.
count:
the numbers of A/D conversion
ad_buffer:
the start address of the memory buffer
to store the AD data, the buffer size
must large than the number of AD
conversion.
c1:
the 16-bit timer frequency divider of
timer channel #1
c2:
the 16-bit timer frequency divider of
timer channel #2
@ Return Code
ERR_NoError
ERR_BoardNoInit, ERR_InvalidADChannel,