Drive communication is an RS-485 serial link between the Variable Frequency Drive (VFD) and the Stagehand Control Card (SCC) inside a Stagehand. The VFD and SCC communicate by the Modbus protocol allowing the SCC to gather information and send it to Spikemark. With this Modbus link Spikemark can view detailed drive faults, reset the VFD, auto tune and analyze the current and frequency for a given movement.