predetermined maximum number of input vin data sets may be greater than or less than 90 without departing from the scope and spirit of the present invention for example upon enlargement of the input buffer memory capacity the predetermined maximum number of vin data sets may be increased to permit uninterrupted operation of the stamping center 108 for two hours four hours or more as desired when the vin data acquisition mode select 118 is in the u201c auto u201d setting 120 the vin data sets stored in the plc input buffer memory 112 are sequentially or serially made available to the stamping center controller for use in a stamping operation when any particular vin data set is accessed by the stamping center 108 the remaining number of vin data sets stored in the plc input buffer memory 112 is reduced by one the number of vin data sets stored in the plc input buffer memory 112 is monitored 122 and when the number reaches or falls below a predetermined minimum number the plc 102 sends a request for another lot of vin data sets to the main computer 100 via the communications interface 106 and the network connection 104 if communication between the plc 102 and the main computer 100 via the communications interface 106 and network connection 104 are available 123 the plc 39 s request for another lot of vin data sets is sent immediately otherwise the request is held until the communications are reestablished preferably the predetermined number of vin data sets is the number that is required to permit uninterrupted operation of the.