LaserWriter
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| LaserWriter | |
| Introduced: | March 1, 1985 |
| Discontinued: | February 1, 1988 |
| Cost: | $6,995 |
| Processor: | Motorola 68000 |
| Frequency: | 12 MHz |
| Minimum: | 1.5 MB |
| Maximum: | 1.5 MB |
| Slot: | 1 |
| ROM: | 512 kB |
| Ports: | Serial, LocalTalk |
| Type: | Laser |
| Color: | 1 |
| DPI: | 300 |
| Speed: | 8 Pages Per Minute |
| Language: | PostScript Diablo 630 |
| Power: | 760 Watts |
| Weight: | 77 lb |
| Dimensions: | (H x W x D) 11.5 x 18.5 x 16.2 in |
The Apple LaserWriter was one of the first laser printers available to the mass market. The combination of the LaserWriter printer, publishing software Aldus PageMaker, and the GUI-based Macintosh, is considered by some to have sparked the desktop publishing (DTP) revolution.
[edit] History
When it was introduced in late 1985, the LaserWriter was the first laser printer for the Macintosh. With a printer resolution of 300 dpi and printing speed of 8ppm, the LaserWriter may have seemed like just another ordinary printer. But at the heart of the Laserwriter's raster image processor lay the Adobe PostScript interpreter, a feature that would ultimately transform the landscape of computer desktop publishing.
The original LaserWriter used a Canon LBP-CX print engine [1], which was used by many printer manufacturers at the time. The print engine is responsible for feeding paper, image transfer, and fusing the image. Parts from early LaserWriter and HP LaserJet printers are sometimes interchangeable, as they were often based on the same print engine.
Unlike HP's PCL and other early printer control languages, PostScript was a complete page description language. PostScript described fonts in outline form, an attribute allowing arbitrary size, rotation, and position. PostScript handled bitmap graphics and vector graphics equally well, allowing any mixture of fonts, bitmaps, and drawing primitives on a single page (limited by the PostScript interpreter's available RAM). While competing printers offered some of these capabilities, they were limited in their ability to reproduce free-form layouts (as a desktop publishing application might produce).
The use of PostScript did not come cheap. At an introductory price of US$6,995, the LaserWriter was more expensive than PC laser printers of comparable print speed and quality. The LaserWriter's high cost was largely due to the extra processing power needed to run the PostScript interpreter. As it was a complete programming language, PostScript came saddled with the overhead of a complex software rasterizer program (running inside the printer). Powering the LaserWriter was a Motorola 68000 CPU running at 12 MHz, 512KB of workspace RAM, and a 1 MB framebuffer. At introduction, the LaserWriter had the most processing power in Apple's product line — more than an 8MHz Macintosh.
Since the price of a single LaserWriter cost many times that of a dot-matrix impact printer, some means to share the printer with several Macs was desired. LANs were not yet widespread, being both complex and expensive, so Apple developed its own networking scheme, LocalTalk. Based on the AppleTalk protocol stack, LocalTalk connected the LaserWriter to the Mac over an RS-422 serial port. At 250 kbit/s, LocalTalk was slower than the Centronics PC parallel interface, but offered the advantage of sharing a single LaserWriter over multiple Macs.
The built-in ability to function in workgroups greatly enhanced the LaserWriter's value proposition. Connectivity, versatility, and WYSIWYG laser quality formed a winning combination in the LaserWriter. Apple's gamble with PostScript paid off handsomely. PostScript enabled the LaserWriter to print complex pages containing high-resolution bitmap graphics, outline fonts, and vector illustrations. Compared to the HP Laserjet and other PCL printers, the LaserWriter could print more complex layouts. Paired with the program Aldus PageMaker, the LaserWriter gave the layout editor an exact replica of the printed page. For high-volume publications, the LaserWriter offered the perfect proofing tool. For the low-volume desktop publisher, the LaserWriter could serve as the master copy. The Mac platform quickly gained the favor of the emerging desktop-publishing industry, both low and high, a niche area the Mac retains importance to this day.
Millions of LaserWriter units were eventually sold, and it is often credited as having saved the Macintosh platform and the Apple company. Building on the success of the original LaserWriter, Apple developed many successive models. Later LaserWriters offered faster printing, higher resolutions, Ethernet connectivity, and eventually, color output. To compete, many other laser printer manufacturers licensed Adobe PostScript for inclusion into their own models.
Eventually, the standardization on Ethernet and PostScript as a means for connecting to and controlling laser printers rendered Apple's printers superfluous. The Mac platform functioned equally well with any non-Apple Postscript printer. After the LaserWriter 8500, Apple discontinued the Laserwriter product line.
[edit] Trivia
The LaserWriter has an interactive PostScript interpreter: one can actually connect a serial terminal to the printer and, by typing "executive", communicate with the printer's computer. The printer will also display diagnostic error messages on this link. (RS-232, 19200 baud, 8 bits, no parity bit, 1 stop bit.)
Older LaserWriters have a spring-loaded tray to feed paper. It is designed to move up a little when a page feeds, but is inherently flawed because this makes the printer feed 2 or 3 pages at a time occasionally, resulting in a jam.
[edit] External links
| Apple printers | |
|---|---|
| ImageWriter: | II • LQ |
| StyleWriter: | II • 1200 |
| Color StyleWriter: | Pro • 1500 • 2200 • 2400 • 2500 • 4100 • 4500 • 6500 |
| LaserWriter: | Plus • IISC • IINT • IINTX • IIf • IIg • 4/600 PS • 16/600 PS • 12/640 PS • 8500 |
| Color LaserWriter: | 12/600 PS • 12/660 PS |
| Personal LaserWriter: | SC • LS • NT • NTR • 300 • 320 |
| LaserWriter Select: | 300 • 310 • 360 |
| LaserWriter Pro: | 600 • 630 • 810 |
| Other: | SilenType • Scribe Printer • Color Printer • Portable StyleWriter |
