Status LEDs

LED locations

The board has three groups of status LEDs:

  1. Power and ENA on the bottom-left;

  2. TX/RX for RS-489 connnection 1 (UART0/1)

  3. TX/RX for RS-489 connnection 5 (UART5)


Power, ENA and ESTOP

The power indicator is on when power is supplied to the HUB75HAT (either by the RPi or the 5A-75B). When this LED is on, DO NOT unplug the GPIO connector, as this may lead to irreversible damage to the RPi and/or 5A-75B.

The ENA indicator is on when the board got the _enable_ command from LinuxCNC. When this LED is on, signals from the 5A-75B will flow to the three I/O connectors. It is strongly recommended not to change connections from the I/O, as this may result in damage or unexpected movement of the machine.


In version 1.0 the ENA-LED is not working.

TX/RX status LEDs

Both RS-485 connectors have two LEDs indicating communication to and from the port.