PC/104 Bus News
Return to News

Jan 22, 2003 11:00 AM

From ACCES I/O Products, Inc.

New PC/104 Isolated Digital Input / Relay Output boards with Change of State Detection.

Contact Name: Marty Wingett
Contact Email: mwingett@accesio.com
WebSite: http://www.accesio.com/go.cgi?p=../104/104-iiro-16.html


High-Density 32-Channel PC/104 Board Provides Change-of-State Detection, Optically Isolated Digital Inputs, Relay Outputs and Low Cost 
 
ACCES I/O Products, Inc. introduces its Model 104-IIRO-16, a low cost 32-channel PC/104 utility board featuring change-of-state detection and 60V optical isolation on the input lines, and standard Form C SPDT relay outputs. The isolated, non-polarized inputs may be driven by either DC sources of 3-30V (or higher by special order) or AC sources at frequencies of 45Hz to 10KHz. Optically isolating the digital inputs from each other, and from the computer, assures smooth, error-free data transmission even in noisy, real-world environments. The 16 input channels are available via a 34-pin header, while the relay outputs are available via an industry-standard 50 pin IDC type header. 
 
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 board’s typical response time to 10 usec when used with faster DC inputs. The input impedance is 1.8K Ohm to accommodate a wide input range.  
 
The Model 104-IIRO-16 board is installed by jumper selecting base addresses and IRQ. System interrupts are software controlled, enabling the board to generate an interrupt whenever one or more of the isolated digital inputs changes state. Once a latched interrupt has been generated and serviced, the board’s inputs are read to determine their status, then the interrupt is automatically cleared. This eliminates the need for constant polling and greatly frees up system resources.  
 
The board also provides sixteen Form C electromechanical relay outputs. All relays are de-energized at system power-up to prevent generating an unintended control output signal. Data to the relays are latched. 
 
The Model 104-IIRO-16 isolated digital input and relay output board is designed for use in industrial environments of –40 to +70C (non-icing). The board may be installed in any standard PC/104 motherboard slot or stack, and is available with optional cables (CAB50F-6, and CAB40F-6), screw termination boards (STB-50 and STB-37) and snaptrack for mounting both of the screw termination boards. 
 
The board comes with a CD containing utility and tools software, an illustrated set-up program for configuring jumpers, and card-specific demonstrations for programming the relay outputs, reading the inputs, and implementing the change-of-state interrupt feature. Source code and examples in “C” are provided for Linux and DOS, and in a variety of languages for use in Windows versions up to XP.