Abstract: A keyboard system for chord entry keying of alphanumeric data fields includes decoding logic permitting substantially or near-simultaneous depression of numeric or alpha data keys and entry or function keys. The logic provides a decoding algorithm for resolving simultaneous entries by utilizing one or another rule of time of key depression. Depression of a numeric or alpha key within 60 milliseconds of an entry key is permitted for decoding of the data as the last key of the current data field. In a time frame between 60 and 100 milliseconds, a warning tone is received for purposes of verifying the last data field entry and to allow the operator to monitor timing performance.