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104-II32-4RO PC/104 Isolated Input/Relay Module, 32 Iso In/4 Relay out

Acces I/O



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Product Datasheet

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Please note, Acces I/O products are often available in an array of different options, of which only a selection will be displayed here. Please contact us for pricing if you require a product option that is not shown on our website.

Model 104-II32-4RO is a 36-channel PC/104 utility board featuring 32 fully optically isolated digital inputs and four handy relay outputs. The inputs may be driven by either DC sources of 3-31V (or higher by special order) or AC sources at frequencies of 40Hz to 10KHz. Optically isolating the digital inputs from each other, and from the computer, assures smooth, error-free data transmission in noisy, real-world environments. All I/O connections are made via one 34-pin and one 50-pin right angle header (vertical headers available upon request).

Each input circuit includes a jumper selectable slow/fast filter to accommodate AC inputs and is also useful for slow DC inputs in noisy environments. The filter may be manually disabled to increase the boards typical response time to 10 usec when used with faster DC inputs. The input impedance is 1.8K Ohms to accommodate a wide input range. To prevent erroneous input state change detections and interrupts, Schmitt triggers are used which provides a solid logic signal to the computer interface.

The electromechanical relays are more flexible than FET and solid state outputs in regards to the kind of signals that can be switched. Another cool feature of the board is a fused +5V at the connector which can be used with a wrap plug for an easy test setup to quickly verify proper operation of the boards 32 inputs, change of state detection IRQ inchs and 4 relays without any additional test equipment!

System interrupts are software controlled, enabling the board to generate an interrupt whenever one or more of the isolated digital inputs changes state. When an interrupt is received a provided ISR (Interrupt Service Routine) handles the request, polls the card once to read the state change then clears the interrupt, enabling the board to detect the next change without processor intervention. IRQ Sharing with other ISA system devices is enabled for ease of system development and installation.

This 8-bit (16-bit pass through connectors) PC/104 board can be installed in any embedded system that supports PC/104 or PC/104+ modules. I/O connectors ship standard as right angle pin type but can also be ordered as vertical to avoid obstructions by other system components or enclosure constraints. This high-density I/O board is available with a variety of options such as an economy version (no-COS), extended (-40 to +85 C) temperature, higher input ranges, without relays, etc. Let us know what you need for your OEM application and we inchll supply it, saving you time and money by buying only what you need.

The 104-II32-4RO is supported for use in most operating systems and includes a free DOS, Linux and Windows 95/XP/2003/2008/7/8/8.1 compatible software package. This contains sample programs and source code in Visual Basic, Delphi, and Visual C++ for Windows. Also incorporated is a graphical setup program in Windows. Third party support includes a Windows standard dll interface usable from the most popular application programs. Linux support consists of installation files and basic samples for programming from user level via an open source kernel driver.