Returns the connection state of the on-board reference Clock to the PXI reference Clock.
GxCalGetRefClockToPxiRefClockState (nHandle, pnState, pnStatus)
Name |
Type |
Description |
nHandle |
SHORT |
Handle to a GX1164 board. |
pnState |
PSHORT |
Reference Clock to PXI Reference Clock state:GXCAL_REF_CLOCK_TO_PXI_REF_CLOCK_OFF: Disconnect the on-board reference Clock from the PXI Reference Clock.GXCAL_REF_CLOCK_TO_PXI_REF_CLOCK_ON: Connect the on board-reference Clock to the PXI Reference Clock. |
pnStatus |
PSHORT |
Returned status: 0 on success, negative number on failure. |
The PXI chassis has a 10 MHz clock line (PXI_CLK10) in its backplane that allows devices plugged into the non-star controller slots (slots 3 and higher) to phase-lock their oscillators to the backplane clock. A single backplane clock can control this way the drift in the oscillators on all the devices in the non-star controller slots. The GX1034 board, when plugged into the star-controller slot (slot 2) can replace the PXI backplane clock with its much more stable oscillator. Alternatively, when plugged into one of the non-star controller slots (slots 3 and higher), the GX1034 board can be programmed that its clock source will use the PXI backplane clock see the GxCalSetClockSource function for details.
This call is valid only if the GX1034 board is plugged into the star-controller slot (slot 2) of the PXI chassis.
The following example returns the connection state of the on-board reference Clock to the PXI reference Clock:
SHORT nState;
GxCalGetRefClockToPxiRefClockState (nHandle, &nState, &nStatus);