Overview.
This card has been designed to provide a flexible interface and functions to your computer projects, by using the parallel port control software. This board provides a faster way to connect devices and reduce the possibility of wiring errors.

Features

• Fully optoisolated The card isolates connections to protect your computer from short-circuit. An opto-isolator is an integrated circuit that transmits the signal through an encapsulated LED and phototransistor. When the signal is on, the LED lights up, the phototransistor captures it and relays the signal. In that way, your computer’s electronics are completely isolated from the cnc circuitry. The signals are transmitted through light and not through physical connections. In this way, a power surge has no way of reaching your computer. That is the reason why this card has two power connections. One power connection is power powering the circuit that interacts with the PC, the other connection is for powering the circuit that interacts with your cnc system. Extra precautions have been taken when designing this circuit, by taking into consideration the extremely high voltages that stepper drivers can achieve and lack of experience that some users could have in wiring circuits of this kind.

• Buffered outputs. All inputs and outputs are buffered through the use of high speed and high power buffers. Each pins deliver 24 milliamps.

• PULL-UP or PULL-DOWN selection for inputs. Includes jumpers to select the best input configuration for your application.

• IEEE 1284 Standard compatible. Includes the circuitry recommended by the IEEE 1284 Level 1 standards for bidirectional parallel communications between personal computers and peripherals

• The common terminal to pins 2-9 can be ground or +5vdc. The board has a jumper that allows you to select if the common terminal to pins 2-9 will carry a ground or +5vdc. So if you are connecting encoders or proximity switches, you can select it to ground. If you are connecting Geckodrives or limit switches, you can set it to be +5vdc.

• Support for up to 1MHz optoisolation on step and direction signals. New on this revision is that the optoisolation circuit has been optimized and now supports full optoisolation at speeds up to 1MHz.

• All pins can be used in a concurrent manner. You can use all the input or output pins in a concurrent manner. For example, if you are using output pin #1 to control the Built-in Solid State Relay Board, you can also access that signal from the output pin on the board or from the DB25 connector for output. Each connection will not affect the other current from the other connection.

• Built-in Passive Low Pass Filters for the all signal. This board includes low pass filters to reduce the effect of the noise from the drivers or other devices over the signals.

• External Enable Pin (EN). The board has a pin that allows you enable/disable all the outputs at once. The board requires +5vdc in the EN pin. If it is not present, it will send all the outputs to ground immediately. You can use this enable and disable your system manually, or you can install an external Safety Charge Pump or other external device.

• Status LEDs on all inputs and output connections. No more guessing. You can SEE all your signals. Save valuable time and brainpower for cncing.