Simple Electrical Transducer (SET) Standard
Trace Center Project Team:
Joseph M. Schauer, BSEE; David P. Kelso, MS; Gregg C. Vanderheiden,
The Trace Center first became involved in the
standardization area in order to deal with the
problems encountered with user interfaces to
communication, control, and computer access aids. At
the time, there were approximately 65 specialized
interfaces commercially available. Unfortunately, no
two manufacturers, even by accident, chose the same
connectors or connector pin assignments for their
controls. As a result, clinicians were restricted to
the use of only a small number of these interfaces,
since the interfaces were not interchangeable across
aids without rewiring either the interface or the aid.
The Trace Center initiated an effort and, working with
manufacturers and researchers from North America,
Europe and Japan, developed a Simple Electrical
Transducer Interconnection Standard (SET standard). The
original SET efforts led to an initial voluntary
standard (SET Version 0.2), which was agreed to by a
group of manufacturers. Since its introduction, about
80% to 90% of controls and devices addressed by the SET
have conformed to most or all of the specifications.
During 1987-88, a revision of the first standard was
issued (SET Version 1.0), taking into account the
suggestions and comments received from the field.
[Figure 1 under the Simple Electrical Transducer (SET)
shows the pin out descriptions for a 9 pin D male
connector and a two 3.5 mm miniature phone plugs.
The 9 pin male connector pin numbers would be assigned
to follow the SET standard as follows:
Pin 1 is switch A, row 1, or rheostat G
The 3.5 mm mono phone plug would have the tip act as
switch A and the shell would act as the switch common.
The 3.5 mm stereo phone plug would again have the tip
act as switch A, the ring act as switch B, and the
shell would again act as switch common.]
Pin 2 is switch B, row 2, or rheostat F
Pin 3 is switch C, row 3, or rheostat E
Pin 4 is switch D, row 4, or rheostat D
Pin 5 is switch F, column 1, rheostat B
Pin 6 is switch E, column 3, rheostat C
Pin 7 is rheostat common
Pin 8 is switch common
Pin 9 is switch G, column 2, rheostat A
The SET Standard seeks to standardize: (1) the physical
connections between user controls and
electrical/electronic aids; (2) the electrical
specifications of the interfaces between controls and
aids; and (3) the categorization and labeling of
controls and aids as to their electrical makeup.
The standard has been circulated as a working paper
among interested parties. The document is distributed
through the Trace Center Reprint Service. The document
lays out all aspects of the standard as simply as
possible while still remaining accurate. Appendices
provide a quick reference to pin assignments for
A final version of the SET is completed and in use by
manufacturers in the augmentative communication field.
The Trace Center distributes the standard through its
Reprint Service, and answers questions from
manufacturers regarding compliance with the standard.
The Trace Center will continue to support other
organizations in their adoption of the SET standard.
Future revisions or expansions of the standard may also
be undertaken, but none are now planned.
Rodgers, B. L., Kelso, D. P., & Vanderheiden, G.
C.(1984). Simple electrical transducer (SET) standard,
proposal 0.2. Madison: University of Wisconsin, Trace
Research and Development Center.
Schauer, J. M., Kelso, D. P., & Vanderheiden, G.
C.(1988). Simple electrical transducer (SET) standard,
version 1.0. Madison: University of Wisconsin, Trace
Research and Development Center.
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