1. A special high speed chip is used to process the input and output (I/O) signals. It is capable of making the machine work stably, with the features of correcting and enlarging the signals that removing the unnecessary disturb signals. 2. The computer port supplies the power individually, separating from the power supply of other parts. Therefore, the computer and machine tool isolate effectively. It makes the data more secure, with further insurance of security and stability. 3. There are 5 input signals, communicating with the host computer, which are isolated by the optical coupling. Among the optical coupling isolation, the P11and P12 are high-speed, which can be used for connecting main shaft encoder, or the same demanding signal as hand wheel A, B. 4. There are 12 output signal, which is allowed to controlling output, supporting as many as linkage. Some of the output port is reusable functinality. Meanwhile, one port only can be used as one function. 5. This board only support port,if your laptop does not have its own parallel port,you need purchase a PCI converte Card. Wide input voltage power supply: 15-32VDC. The function of preventing reverse connection protection. 2 groups of output voltage: 5V and 12V voltage, 100MA output capacity. Power supply voltage has a range: 15-50VD. Increase isolated power module. Do not insert the USB line to the computer's USB port. Just insert a line. It is more convenient and reliable. The current output ability of 5V and 12V voltage output can upgrade to 200MA. 1. There are 3 replays, P2, P3 and P4, which can support control software programming. The relay's on or off can be controlled through the control of software. Each relay has attracted indicating lamp, which is more intuitive and convenient. The 3 relays can be used to control the opening and closing of the liquid coolant, mist coolant, liquid state coolant and so on. They can also be used to control the electromagnetic valve device power switch. P2 port is for the spindle, P3 port is for the cooling liquid, P4 port can be defined. 2. The high speed optical coupling isolation is used to control the rotational speed of spindle. The output port is parallel port P1, which can output the PWM signal within 2.5KHZ. On the interface board ,there is a D/A circuit, with PWM to a 0-10V. The circuit can output 0-10V level to control the inverter which only has analog speed control in the market. Thus it can control the rotational speed of the spindle. It is important that the PWM output and 0-10V output can only choose one in two. They can't be used at the same time. 3. Interface board can be connected with the cathode or total output to the stepper drive, or servo drive (servo driver must support the digital signal).The output is the 5Vlevel. Colour: as shown Material: ABS Size: 7.5 x 11 x 3cm Package Contents: 1 x Stepper Motor Controller Board Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.