This manual contains all of the information necessary to operate, configure, maintain, and troubleshoot the 7421 bar code label Printer This manual was written for all users who need to know how to use the Printer to print labels. What You Will Find in This Manual This table summarizes the information in each chapter of this manual: For Information On Refer To Operating the Printer Chapter 1, “Operating the Printer ” Explains the Printer front panel, tells you how to load media for self-strip, load fanfold media, and insert the optional memory card. Configuring the Printer Chapter 2, “Configuring the Printer ” Explains how to configure the Printer for optimal performance. You will learn how to set the media sensitivity number, the print darkness, adjust the label sensors, and print a test label. Routine maintenance Chapter 3, “Maintaining the Printer ” Shows how to maintain the Printer Troubleshooting Chapter 4, “Troubleshooting.” Instructs how to clear error messages and troubleshoot programming or configuration problems Printer pecifications and options Appendix A, “Printer Specifications.” Lists the specifications for the Printer the available options, and the supported symbologies. Communications Printer protocols, and Printer interfaces Appendix B, “Communications Reference.” Defines the communications protocol and the interfaces that the Printer uses to communicate. Character sets Appendix C, “Character Sets.” Contains tables for the character sets that your Printer upports.