Measure duty cycle with a counter?

[DLazarski]

I'm trying to measure duty cycle but I'm getting inconsistent results. With a function generator sending 70% duty cycle signal, I randomly get 30%. Looking at the buffer, it looks like device is starting the counter while the signal is low and not high so I end up being off by one semi period but I have no way of determining that. Is there a way to configure the card to always start measurement when signal is high?

Here's the code in VB6 showing how I'm configuring it.

    er = GPCTR_Control(m_uiDeviceNumber, ND_COUNTER_0, ND_RESET)
    er = GPCTR_Set_Application(m_uiDeviceNumber, ND_COUNTER_0, ND_BUFFERED_SEMI_PERIOD_MSR)
    er = GPCTR_Config_Buffer(m_uiDeviceNumber, ND_COUNTER_0, 0, 22, Buffer&(0))
    er = GPCTR_Change_Parameter(m_uiDeviceNumber, ND_COUNTER_0, ND_SOURCE, ND_INTERNAL_100_KHZ)
    er = GPCTR_Change_Parameter(m_uiDeviceNumber, ND_COUNTER_0, ND_SOURCE_POLARITY, ND_LOW_TO_HIGH)
    er = GPCTR_Change_Parameter(m_uiDeviceNumber, ND_COUNTER_0, ND_GATE, ND_PFI_9)
    er = GPCTR_Change_Parameter(m_uiDeviceNumber, ND_COUNTER_0, ND_GATE_POLARITY, ND_LOW_TO_HIGH)
    er = GPCTR_Change_Parameter(m_uiDeviceNumber, ND_COUNTER_0, ND_INITIAL_COUNT, 0)
    er = GPCTR_Control(m_uiDeviceNumber, ND_COUNTER_0, ND_PROGRAM)

Any help would be appreciated. Thank you.
-Dom

[Kevin_Price]

Duplicate thread, answered here.

-Kevin P.