4 general-purpose isolated relay drive output interface can drive four relays for controlling the spindle starts forward rotating and reverse rotating pumps and other device.4 general-purpose inputs you can connect the limit switch estop switch probe switch back to zero and other device.Have 0-10V output port you can use mach3 software to control the spindle motor speed.Need use external 24V DC power supply to isolate USB and external port and to make the system more stable.Support for connecting electronic handwheel.Maximum step-pulse frequency is 100KHz which is suitable for the servo or stepping motor.Support for 4-axis linkage you can connect four stepper motor drives or servo drives.CNC USB MACH3 100Khz Breakout Board 4 Axis Interface Driver Motion Controller Features: The card can run what all other MACH 3 controllers can run and supports the drive shaft and the driven shaft gantry supports automatic leveling and has an output pulse 100 KHz. This 4 Axis CNC USB Controller is designed to be used for notebook and tablets simple configuration and compatibility.