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     CCITT V.24     Known as EIA RS-232 in the USA.  V.24 defines only the
                    functions of the circuits.  EIA-232-E (which is how the
                    current version of the standard is designated) also
                    defines electrical characteristics and connectors.  The
                    232-equivalent electrical characteristics and connectors
                    are defined in ISO 2110. | 
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