INPUT/OUTPUT CARD
IOCARD - 1

USE

IOCARD-I lnput/Output Card is designed to be used for the remote control of various devices to include lamps, relays, sensors, A/D converters, low power motors etc.
Remote control is effected usually by cable. The output signals are transferred to the devices either directly or through the appropriate driver.

TECHNICAL DESCRIPTION

Basic Structure.
IOCARD-I consists of a conventional robust printed circuit board (PCB), a part of which is specially formed with tinned connecting terminals, to fit the ISA port of an IBM compatible motherboard. The electronic components are fixed on the PCB and include: eight input opto-isolators, eight output opto-isolators, the buffer, the register, thirty two surface mount technology resistors, two capacitors, eight dip-switches (jumpers), two switch connectors and a 25-pin socket.

Main functional units.
Components are functionsally grouped to the following parts:
The Input part.
The Input part consists of 8 opto-couplers (or opto-isolators) - that form an 8 line bus. The photo-transistor part of the opto-couplers are connected to a 12 or 24VDC external power supply that is used for the input signals. When the opto-isolator is not grounded (thus its circuit is open) it is interpreted as the "logical value" 1, whereas when grounded (thus the circuit is closed) it is interpreted as the "logical value" 0. The "grounding" can be done by either switches, A/D converters, sensors or other circuits and represents the input signals.
The Output part.
The output part consists of 8 opto-couplers (or opto-isolators) - that form an 8 line bus. The diode part of those opto-couplers are connected to an 8 bit DAT latch register. Every photo-transistor in these opto-couplers is serving as one output of the Card and is connected to the device load we want to control, either directly or via the appropriate driver, which is powered by an external power source. The "logical value" 0 activates the photo-transistor, so the
circuit that includes the device load is closed and current flow is developing. On the contrary, the "logical value" 1 corresponds to an inactive photo-transistor, so no current flow is developed and the circuit that includes the device load remains open.
Please notice that both input and output units (parts) are receiving the +5V voltage, required for their operation, by the computer's build in power supply.
The dipswitches (jumpers).
There is a set of 8 line dipswitches which is assigned to provide an address for establishing communication of the IOCARD-I with the computer.
The software.
The software provides the way that the input and output signals are handled, thus making it possible to determine the response of the controlled
peripherals that are connected to the outputs. This software is developed to satisfy the needs of a specific application each time and is written in either PASCAL or C++ programming language.
LT-P can supply to the interested parties single IOCARD-I units or with the appropriate software in Pascal or C+ +, tailored to satisfy your particular needs, in short notice.

TECHNICAL CHARACTERISTICS IBM ISA port compatibility Complete optical isolation (opto-couplers) from external circuits High noise immunity Use of only one address of the address space Optical input current: 10mA 8 bit input / 8 bit output buses High reverse voltage immunity Output optical max current: 130mA Output type 1: opto-couplers with common anode Output type 2: opto-couplers with an open collector Voltage applied to output collector : =/< 200V Input opto-couplers susceptibility : 2MHz Address setting realized by 3 switches