USB LED Descriptions
The USB serial two and four-port hardware uses bicolor LEDs to indicate device and port status. The following table describes these LEDs; the following figure shows their location.
| LED | Description |
|---|---|
| Ready | Dim Red—Powered, but not connected to USB (USB-485/4 only) Red—Powered and connected to USB, but not fully configured Yellow—Device is ready (normal operation) Blinking Red or Red-Yellow—Device error. Contact NI. |
| Port x | Solid Red—Port is open, but no valid signals detected (USB-232 only) Solid Green—Port is open Blinking Yellow—Port is transmitting Blinking Green—Port is receiving Alternated Blinking Green/Yellow—Port is transmitting and receiving Blinking Red—Port error (framing error, FIFO overrun, or parity error) |
| 1 | READY LED |
| 2 | PORT LEDs |