Technical Reference Manual This manual is a supplement to the complete Hewlett-Packard PCL/ PJL Technical Reference Library (Part #5021-0330). Hewlett-Packard recommends you order this documentation package, as it will aid you while using the D640 Technical Reference Manual. The D640 Technical Reference Manual describes differences between the D640’s implementation of PJL and PCL and implementations on other HP Printer As such, it is not an exhaustive reference for those languages, but a supplement to these books: l PCL 5 Printer Language Technical Reference Manual l Printer Job Language Technical Reference Manual l PCL 5 Comparison Guide l Printer Language Technical Quick Reference Guide. This manual was written for experienced users, such as application developers and technical support personnel. Before using the manual, programmers should be familiar with the reference manuals mentioned above. Other D640 Manuals The information in this manual supplements the following HP D640 documents: l Model D640 Installation Manual l Model D640 User Manual l Model D640 Enhanced Features Manual l Model D640 Technical Reference Manual l PostScript Emulation Manual for Model D640 Printer