|Model 826 | PCI Express Analog and Digital I/O|
Sensoray's model 826 is a versatile analog and digital I/O system on a PCI Express board. It has 48 digital I/Os with edge capture, sixteen 16-bit analog inputs, eight 16-bit analog outputs, and six advanced counter/timer/encoder channels. An onboard watchdog timer and "safemode" controller work together to activate fail-safe operation in response to faults or external events. The board's high performance, compact size, and abundant resources make it ideally suited for a wide range of measurement and control applications.
The board's analog circuitry employs fully electronic calibration; no mechanical trims are needed. On-board non-volatile memory stores factory-programmed calibration values so that boards can be easily and quickly installed.
Five low-profile headers convey all I/O signals to external circuitry, enabling the board to easily fit into high-density systems. The board's mounting bracket features a cable hold down to keep wiring organized and secure. Sensoray offers a variety of cables and signal breakout solutions to connect the board to field wiring.
A free software development kit (SDK) is available for model 826. The SDK includes a high performance application programming interface (API) that provides access to the board's myriad I/O resources. The API supports both polled and event-driven operation to facilitate both single and multi-threaded applications. Comprehensive documentation and sample programs are included to help speed development.
Counters and Encoders
Each of the six counter channels can operate as a conventional timer/counter or in any of several special modes. The advanced architecture enables a single channel to completely implement common applications such as incremental encoder interface, pulse generation, PWM generation, frequency measurement, period measurement, or pulse width measurement.
Clock inputs may be driven by internal or external sources, and external clocks may be either single phase or quadrature encoded (e.g., incremental encoder). Each channel accepts differential RS-422 or single-ended TTL/CMOS signals on dedicated clock and index input pins. In addition, counter output and enable input signals can be routed to digital I/O channels if needed.
Sixteen differential input channels are multiplexed and routed to a programmable gain amplifier and 16-bit analog-to-digital converter. Each channel may be software configured for an input voltage range of ±1V, ±2V, ±5V, or ±10V.
A conversion list specifies the channels that are to be digitized in rapid succession (i.e., in a "burst") whenever a conversion is initiated. Conversion bursts can be software or hardware triggered, or the analog input system may be configured to "free run" so that it continously performs back-to-back bursts.
The board has eight 16-bit, single-ended digital-to-analog converter channels. Each channel can be configured for an output range of 0 to +5V, 0 to +10V, ±5V, or ±10V. All analog outputs are programmed to zero volts upon board reset.
Each open-collector digital I/O (DIO) channel can operate as an input, an output, or in wired-OR mode. Edge detection and capture is supported on all channels. The API allows the application program to wait for either the first edge event or all edge events occuring on any arbitrary set of channels.
50-pin headers are used to connect the DIOs to standard solid-state relay (SSR) racks, standard breakout boards, or custom OEM signal distribution systems. All DIO outputs are turned off upon board reset.
The board has a multistage watchdog timer that can activate fail-safe operation and generate service requests. The watchdog has three timer stages that generate events in sequence according to user-defined timing. Each event can be configured to generate an internal service request or activate an external digital output signal.
A built-in "safemode" controller will force analog and digital outputs to predetermined, configurable "safe" levels in response to hardware triggers. The controller works in concert with the watchdog timer and external devices such as emergency shutdown contacts to switch the board's outputs to fail-safe levels without software intervention.
Sensoray offers a variety of solutions for routing I/O signals to external field wiring. The breakout and SSR boards listed below are designed to directly connect to the 826's I/O headers via flat cable.