NI PXI/PCI-5401/5411/5431
LOCK and ACCESS LEDs
The NI 5401/5411/5431 signal generators have two LEDs: LOCK and ACCESS.
LOCK LED
The LOCK LED indicates basic hardware status.
| Color | Indications |
|---|---|
| Off | The device phase-locked loop is currently not locked to a Reference clock source. This status is normal if the device has not been programmed to phase lock to a Reference clock source. This is an indication of a problem if the device has not been programmed to phase lock to a Reference clock source. |
| Amber | The device phase-locked loop is locked to the selected Reference clock source. |
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Note For more information, refer to Phase-Locked Loops and Module Synchronization. |
ACCESS LED
The ACCESS LED indicates the device state.
| Color | Indications |
|---|---|
| Green | Indicates that the device is powered. |
| Yellow | Indicates that the computer is currently accessing the device. |