Control Connections

The SPARK Flex can be controlled by three different interfaces: servo-style PWM, Controller Area Network (CAN), and USB. The following sections describe the physical connections to these interfaces. For details on the operation and protocols of the PWM, CAN, or USB interfaces, please see Control Interfaces.

SPARK Flex Control Connections

CAN/PWM Connections

CAN and PWM control connections share a set of four integrated 26 AWG twisted wires extending 45 cm from the case of the motor controller. Each wire is color coded according to its function:

Wire Color	CAN Function	PWM Function
Yellow	CAN High (CANH)	Signal
Green	CAN Low (CANL)	Ground

The wires are terminated with two 1 x 3, 0.1 in pitch, rectangular connectors, both excluding the center pin. One connector is pinned and the other socketed to facilitate daisy-chaining between multiple CAN devices on the bus when using the CAN interface.

Each matching wire pair is physically connected to its functional counterpart within the device. Even if the SPARK Flex loses power, the CAN bus remains unbroken, leaving downstream devices unaffected.

Pay close attention when daisy-chaining devices, and make sure that the colors match from connector-to-connecter along the entire CAN bus. Mismatched connections can cause difficult-to-diagnose communications issues along the entire bus.

When using the PWM interface, only one of the two connectors should be used. In most systems this will be the socketed connector. Therefore, it is best practice to secure the unused wires and protect the exposed pins by covering them with electrical tape.

When daisy-chaining or extending the connections, use the included PWM Cable Clips (REV-11-1229) to secure the two mating connectors together to prevent unintended disconnections.

USB-C Port

The USB-C Port is located above the CAN/PWM wires of the SPARK Flex. It supports USB 2.0 and can provide 5 V power for the SPARK Flex's internal microcontroller.

While you can configure the SPARK Flex under USB-only power, you will not be able to spin a motor unless main power is also connected.

More information about what can be configured and operated through the USB port can be found in the USB Interface section.