Language:
Each printer manufacturer develops its own programming language to control and operate the printer using the computer. Nowadays this information exchange is possible via USB cable, the transmission of the information needed to print can also be transferred wireless. In spite of all this, the so-called printer language plays a major role in transferring information, which are divided into the Printer Control Language (PCL) and Page Description Languages (PDL).
The PCL is hardware specific, which means that most of the devices have their own language for controlling the components of your computer.
The following list shows the most used and most important PCL and its manufacturer/brand:
Virtual print formats are Portable Document Format (PDF) and Variable Print Specification (VPS).
The PDL is a language that reproduces in detail the exact page structure onto output devices such as printers, PC monitors, etc. Such programming languages are based on descriptive text or binary data streams. Furthermore, PDL can describe vector graphic pages and thus is more detailed than the raster graphics.
PDL, in comparison to PCL has less to do with the hardware and is also not a full programming language; the exception is the PostScript language. The PDL has its limitations as the direct commands to control individual components of the PDL printer languages differ from other Printers.
PostScript is an advancement of interPress, which was developed in 1984 by Adobe Systems. It consists of two thirds of a programming language that is very similar to the "FORTH language" and the remaining is responsible for graphics, pictures and other illustrations. Fonts are embedded using vector graphics, and are therefore easier scalable, and are without loss on different output devices. Raster graphics are also applicable in PostScript, they adjust automatically to the output devices by recalculating and scaling to the various output devices. This is enabled by providing the devices, which output PostScript, a so called interpreter that translate the Data into a readable screen graphics. PostScript 3 is going to replace PostScript, with improvements such as enlargement of the color model, called DeviceN, this is the color output device at the exact/precise passes and many others.
HP developed PCL to efficiently manage many printers of their Brand. Around 1984 the first HP LaserJet was developed and for its control the further developed PCL 3 was implemented. PCL has several levels which are advancement of each predecessor, thus helping H printer technique to keep up with their competitor. The versions PLC 1 through PLC 5e/c are sequentially processed by the printer, which means they are processed in the sequence in which they reach the printer. The printer-driver generates its own bit stream for the to-be processed and interpreted data. The success of this language is dependent on its consistency, as the PCL implementation in each HP product (HP Color LaserJet series) is equal.
Details about what was implemented and improved in versions PCL1- 5e/c:
These are the vector graphics commands, which consist of two letter codes. These codes represent the functions of the commands (eg: IN for initialize), followed by one or more parameters to identify the details of processing.
Example:
IN;
SP1;
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=bpl05546#A1 http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=bpl04568 http://cstep.luberth.com/HPGL.pdf http://h20000.www2.hp.com/bc/docs/support/SupportManual/bpl13211/bpl13211.pdf
GDI is a part of Microsoft Windows, and serves as an interface to the graphic devices (the printer). GDI controls the presentation of characters, managing color palettes and is responsible, among other things, to draw lines and curves. The graphic output from the GDI is very slow because most of the elements for the presentation and drawing run through the processor. The changes that have taken place in the Windows operating system, caused an effect on the speed of GDI; Vista slowed down (as opposed to the older versions) the video output because the GDI ran over the CPU and in Windows 7 an acceleration of the GDI's took place due to it running over graphic card instead.
http://classes.engr.oregonstate.edu/eecs/spring2003/ece44x/groups/g1/WhitePaperRichard.pdf
Seiko Epson developed for the control and management of printers in the era of the dot matrix printers. ESC / P gets its name from the escape sequence, in which ESC / P is an introduction to this sequence. Examples can be found in the pdf part 1:
http://support.epson.ru/products/manuals/000350/part1.pdf http://support.epson.ru/products/manuals/000351/part2.pdf