def create_task(self):
# need to check if task exists and fail
#self.task = PyDAQmx.Task()
self.task_handle = mx.TaskHandle(0)
mx.DAQmxCreateTask("", byref(self.task_handle))
if self.mode == 'large_range':
logger.debug('counter_chan {}'.format(self.counter_chan))
logger.debug('input_terminal {}'.format(self.input_terminal))
mx.DAQmxCreateCIFreqChan(
self.task_handle,
counter=str(self.counter_chan),
nameToAssignToChannel="",
minVal=5e1, # applies measMethod is DAQmx_Val_LargeRng2Ctr
maxVal=1e8, # applies measMethod is DAQmx_Val_LargeRng2Ctr
units=DAQmx_Val_Hz,
edge=DAQmx_Val_Rising,
measMethod=DAQmx_Val_LargeRng2Ctr,
measTime=1.0, # applies measMethod is DAQmx_Val_HighFreq2Ctr
divisor=100, # applies measMethod is DAQmx_Val_LargeRng2Ctr
customScaleName=None,
)
elif self.mode == 'high_freq':
mx.DAQmxCreateCIFreqChan(
self.task_handle,
counter=self.counter_chan,
nameToAssignToChannel="",
minVal=1e1, # applies measMethod is DAQmx_Val_LargeRng2Ctr
maxVal=1e7, # applies measMethod is DAQmx_Val_LargeRng2Ctr
units=DAQmx_Val_Hz,
edge=DAQmx_Val_Rising,
measMethod=DAQmx_Val_HighFreq2Ctr,
measTime=0.05, # applies measMethod is DAQmx_Val_HighFreq2Ctr
divisor=100, # applies measMethod is DAQmx_Val_LargeRng2Ctr
customScaleName=None,
)
elif self.mode == 'low_freq':
mx.DAQmxCreateCIFreqChan(
self.task_handle,
counter=self.counter_chan,
nameToAssignToChannel="",
minVal=1e1, # applies measMethod is DAQmx_Val_LargeRng2Ctr
maxVal=1e7, # applies measMethod is DAQmx_Val_LargeRng2Ctr
units=DAQmx_Val_Hz,
edge=DAQmx_Val_Rising,
measMethod=DAQmx_Val_LowFreq1Ctr,
measTime=0.05, # applies measMethod is DAQmx_Val_HighFreq2Ctr
divisor=100, # applies measMethod is DAQmx_Val_LargeRng2Ctr
customScaleName=None,
)
### data = c_int32(0)
### self.task.GetCIDataXferMech(channel=self.counter_chan, data=data )
### print "XFmethod" , data.value
# set DMA
#self.task.SetCIDataXferMech(channel=self.counter_chan, data=DAQmx_Val_DMA)
### self.task.GetReadOverWrite(data=byref(data))
### print "overwrite", data.value
#Set the input terminal of the counter
mx.DAQmxSetCIFreqTerm(self.task_handle,
channel=self.counter_chan,
data=self.input_terminal)
#Set the counter channel to continuously sample into a buffer. The size of the
#buffer is set by sampsPerChan.
mx.DAQmxCfgImplicitTiming(self.task_handle,
sampleMode=DAQmx_Val_ContSamps,
sampsPerChan=1000)
mx.DAQmxSetReadOverWrite(self.task_handle,
DAQmx_Val_OverwriteUnreadSamps)
### self.task.GetReadOverWrite(data=byref(data))
### print "overwrite", data.value
# Sample buffer
self._sample_buffer_count = c_int32(0)
self.sample_buffer = np.zeros((SAMPLE_BUFFER_SIZE, ), dtype=np.float64)
