Chromatographic instrument with command sequencing

A chromatographic instrument for automatically testing specimens against a calibration standard specimen, the instrument comprising receptacle means for retaining in randomly designated locations a plurality of vessels containing specimens including one or more test specimens and a calibration standard specimen, automatic sampling means receptive of specimen location designations for sequentially sampling specimens from selected vessels in the receptacle means, measuring means including a chromatography column receptive of each sampled specimen and measurement instructions for measuring chosen characteristics of each sampled specimen and generating corresponding measurement information, output means receptive of the measurement information for computing and presenting results for each test specimen relative to the standard specimen, a command sequence program for generating a set of command instruction lines in sequence, operational means receptive of the command instruction lines for effecting instrument operation including instructing the sampling means and the measurement means respectively with the specimen location designations and the measurement instructions according to the sequence generated, and storage means for storing operator inputed procedural information including an ordered list of location designations for one or more preselected test specimens, a preselected calibration frequency and the measurement instructions;

• wherein the command sequence program comprises:
• reading means for reading the ordered list to effect a sequential selection of each location designation according to the ordered list;
• command generating means receptive of each sequential selection for generating a corresponding command instruction line containing the location designation and the measurement instructions for each selected specimen;
• line counting means for counting the number of command instruction lines generated since a nearest prior calibration command instruction line or initiation of the command sequence program;
• and calibration placement means receptive of the procedural information and responsive to the counting number being equal to the calibration frequency, for generating a next calibration command instruction line containing the location designation and the measurement instructions for the standard specimen, whereby the set of command instruction lines are sequenced according to the ordered list with at least one calibration command instruction line interspersed therein according to the calibration frequency.