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NEW PRODUCT NEWS—edited by Harv Weiner

Digital I/O Module

The WTDIO-M is a stackable RS-232 data module that provides 14 individually configurable I/O pins. Outputs can sink or source 25 mA and can change logic state upon command. They can also simulate a one-shot (high or low) pulse output with software programmable lengths of 10 to 655,350 ¼S. Inputs can either be polled, or set up to report a logic transition such as that produced by a switch or button wired to ground. An automatic debounce feature masks multiple transitions produced by contact bounce, and typematic repeat is simulated if a button is held down. Data can be read or written to eight I/O pins as a parallel port with a single command. The module also supports a 4 x 4 matrix keypad decoding.

All modules in this series can be plugged end-to-end on a common RS-232 cable attached to the serial port of a host PC. An on-board 32-position DIP switch sets the address of each module, which is used for identifying data transmitted from it, as well as directing data transmitted by the host. The data bus supports full anti-collision discipline between connected modules and will allow up to 32 modules to share the same communications line. Power is supplied by an external 8 to 25 VDC source (not included) to the first module in the chain and is carried down the RS-232 cable to successive modules.The WTDIO-M sells for $49. A data book is available upon request.

Weeder Technologies
(850) 863-5723
www.weedtech.com

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