Abstract: A microprocessor controlled thermal printer particularly usable in a hand-held labeler for printing labels on a composite web detects indices on the web and utilizes the detected indices to position the labels relative to the print head. The printer utilizes an improved index detection system that compensates for variations in index size and density and for variations in sensor sensitivity by detecting both the leading and trailing edges of an index and utilizing the distance between the detected leading and trailing edges to determine the length of the index. By dividing the length thus determined by two, and by advancing the web by this amount after the detection of the leading edge of an index, the center of the index can be accurately located, and the web can be accurately registered at any desired position relative to the center of the index.

Abstract: A printer for printing serial bar codes on a web of record members with a thermal print head is shown. The thermal print head is driven by a series of pulses having a constant duty cycle for each row of information printed. However, the number of pulses in the series is varied from row to row, in accordance with the status of the current row being printed as a bar row or a space row; with the status of at least one row immediately preceding the current row and at least one row immediately succeeding the current row; and with the number of bar rows previously printed. By varying the number of pulses applied to the thermal print head and thus the amount of energy applied thereto, discontinuities in the serial bar code and any information, such as a human readable character, printed adjacent thereto are minimized.

Abstract: A universal controller interface for use in a number of different barcode printers is disposed between the printer's microprocessor and a number of the printer's input and output devices including the printhead. The controller includes a microprocessor interface that allows the controller to be used with various types of printer microprocessors. The controller also includes a printhead control circuit that allows the controller to be used with various types of printheads such as an intelligent thermal printhead or a non-intelligent thermal printhead. The controller also includes a programmable serial input/output port and a programmable baud rate generator so as to further increase its flexibility and use with various types of barcode printer input and output devices. A memory protection circuit of the controller allows various portions of the printer's random access memory to be protected if desired.

Abstract: A printer for printing serial bar codes on a web of record members with a thermal print head is shown. The thermal print head is driven by a series of pulses having a constant duty cycle for each row of information printed. However, the number of pulses in the series is varied from row to row, in accordance with the status of the current row being printed as a bar row or a space row; with the status of at least one row immediately preceding the current row and at least one row immediately succeeding the current row; and with the number of bar rows previously printed. By varying the number of pulses applied to the thermal print head and thus the amount of energy applied thereto, discontinuities in the serial bar code and any information, such as a human readable character, printed adjacent thereto are minimized.

Abstract: A hand-held labeler with an integrally formed optical scanner prints labels with a coded record selected from a plurality of optically scanned and stored coded records. In a data acquisition mode, the optical scanner scans a plurality of coded records, such as bar codes, to generate data representing the coded records for storage in a memory. Selective printing of scanned code and/or information associated therewith is accomplished utilizing a display that is controlled by a keyboard to display information that identifies the data stored in the memory. When information identifying a desired coded record is shown on the display, a print switch may be actuated to cause the code associated with the displayed information to be printed on one or more labels. Further, the scanner may also be used to scan different types of bar codes where each bar code includes a coded information portion and at least one guard code identifying the type of code.

Abstract: A microprocessor controlled thermal printer particularly usable in a hand-held labeler for printing labels on a composite web detects indices on the web and utilizes the detected indices to position the labels relative to the print head. The printer utilizes an improved index detection system that compensates for variations in index size and density and for variations in sensor sensitivity by detecting both the leading and trailing edges of an index and utilizing the distance between the detected leading and trailing edges to determine the length of the index. By dividing the length thus determined by two, and by advancing the web by this amount after the detection of the leading edge of an index, the center of the index can be accurately located, and the web can be accurately registered at any desired position relative to the center of the index.