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5. LED feedback
The Motoron Motor Controller has several LEDs to indicate its status.
Status LEDs
On the edge of the board, opposite the motor output pins, there are two status LEDs.
The yellow status LED indicates reset events and shows when the motor outputs are enabled.
- During the first half second after the Motoron has powered up or its processor has been reset, the yellow LED blinks 4 times.
- Otherwise, if the Motoron motor outputs are enabled or the Motoron is trying to enable them, the yellow LED is on solid. This corresponds to the “Motor output enabled” bit in the “Status flags” variable, which is documented in Section 8.
- Otherwise, if the Reset bit in the “Status flags” variable is set and it is configured to be an error, the yellow LED blinks for 0.5 s once per second. This is the default state, and it generally indicates that communication has not been established.
- Otherwise, the yellow LED blinks briefly once per second.
The red error LED usually indicates hardware issues or errors that prevent the motors from running.
- If you have a Motoron with a UART serial interface and have enabled the “ERR is DE” option, the red LED will only turn on while the Motoron is transmitting a response on its TX line.
- Otherwise, the red LED will be on solid if a motor fault is happening, motor power has been lost, or if there is a firmware-level error stopping the motors from running. More specifically, the red LED will be on if any of the “Motor faulting”, “No power”, or “Error active” flags documented in Section 8 are 1.
- Otherwise the red LED will be off.
If the red LED is off, it does not necessarily mean that the VIN power voltage is high enough for the Motoron to drive motors.
Motor direction LEDs
On the side of the board with the motor output pins, each motor has two direction indicator LEDs.
The green direction LED indicates that the voltage on the MxA pin is high while the voltage on the MxB pin is low. This direction is called forward and corresponds to a positive speed numbers.
The red direction LED indicates that the voltage on the MxB pin is high while the voltage on the MxA pin is low. This direction is called reverse and corresponds to a negative speed numbers.
Both direction LEDs get brighter if the absolute value of the speed increases, or if the motor power supply (VIN) increases.