Indicator Description
| Indicator | Meaning |
| PWR (Green) |
Module power indicator: On: Module is powered normally Off: Module is not powered or powered abnormally |
| RUN (Green) |
Communication indicator: On: Normal communication Off: Abnormal communication |
| RX1/TX1 |
COM1 serial port transmit/receive indicator: the indicator flashes when data is transmitted/received |
| RX2/TX2 |
COM2 serial port transmit/receive indicator: the indicator flashes when data is transmitted/received |
| RX3/TX3 |
COM3 serial port transmit/receive indicator: the indicator flashes when data is transmitted/received |
| RX4/TX4 |
COM4 serial port transmit/receive indicator: the indicator flashes when data is transmitted/received |