Model 2426 is a versatile multi-function I/O board that can be accessed through any TCP/IP-based 10/100 Mbps Ethernet network. It features eight optically isolated digital inputs, sixteen digital outputs, six 12-bit analog inputs, one 12-bit analog output, one RS-422/485 serial communication port, and a high speed incremental encoder interface, all in a compact form factor. With its built-in DIN rail mounts—which enables the board to be securely mounted by simply snapping it in place—and requiring only a single 24VDC power source, the unit can be quickly installed and up and running in minutes.

Telnet/HTTP servers

The board has built-in HTTP and telnet servers that enable any web browser or telnet client to access onboard I/O. These widely available, standardized protocols make it possible to monitor and control the board's I/O interfaces across a network without the need to install any device drivers or other proprietary software. In addition, telnet shell commands and replies are conveyed in plaintext, resulting in dramatically shorter development time and simplified maintenance.

 

Commonly used shell commands
rai	Read analog input voltages
wao	Set analog output voltage
rdi	Read digital inputs
wdo	Set digital outputs
renc	Read encoder counts
com	Connect to the serial port

 

Concurrent telnet sessions are supported so that multiple threads, or even different network hosts, can communicate with the board at the same time. This feature offers a high degree of flexibility that can be leveraged in a variety of ways. For example, support personnel can simply plug into the network and monitor the board's operation over a private telnet session while, at the same time, the board is controlled by a remote automation process running over a different session. Furthermore, the automation process itself is not limited to a single telnet session; for example, it could have two threads--one to handle serial port communications and another to control other I/O interfaces--with each thread operating over its own independent telnet session. Consequently, system design is simplified and resulting systems tend to be robust and easily maintained.

Open source SDK

A software development kit (SDK) is available for the 2426 which includes documentation, sample applications and a comprehensive application program interface (API). The API transparently handles all underlying protocols so the programmer can focus on application development. For example, an application program could simply call the API's s2426_WriteDout() function to update the board's general purpose digital outputs. The SDK includes full source code for the API, including ports for both Linux and Windows, with instructions for OEM customization and porting to other operating systems.

Sample web page interface

 

2426 control page on HTC Hero (Google Android) browser