What are Downloadable PCL Fonts and Why should I care?
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A brief history...
Sending data to a printer used to be a simple,
line-by-line affair: you transmitted up to 80 characters (or up to 132 for a wide-carriage
printer) followed by a carriage return and line feed. The printhead zipped back to the
left margin, the paper moved up and you printed the next line. Earlier printers let you
choose any font as long as it was Courier 12cpi; others offered a small selection of
resident fonts. You could print graphics using special commands (but only one line at a
time).
Then came the laser printer which formatted an entire page in memory before putting
anything on paper. This opened up the possiblity of moving around the page at will to
place text and graphics. Hewlett-Packard developed the Printer Command Language (PCL) to
provide a means for controlling the printer and instructing it how to format pages. The
language evolved from PCL1 to the current version as of this writing, PCL6. Even though
the earliest laser printers offered a wide selection of embedded fonts, users often needed
something more... scientific character sets, special graphics, barcodes, etc.
Hewlett-Packard's LaserJet printers included plug-in slots for font cartridges, making it
possible to add fonts to the printer (Hewlett-Packard's "Bar Codes & More"
cartridge, for example). Current printer models no longer include cartridge slots, but
achieve the same result with internal connectors for the installation of SIMM or DIMM
memory modules.
PCL4 for the first time included the ability to download "soft fonts" into the
printer's memory. A font file could be stored on the host computer and, when needed for a
printout, copied to the printer just ahead of the report data. As long as the destination
printer supported PCL4 or higher, the font would be added to the printer's list of
internal fonts (until the power went out). This meant that printers did not have to be of
the same brand or model and did not have to have a special font cartridge, SIMM, or DIMM
installed.
Can downloadable fonts help me?...
If you are working in Windows or another graphical environment that supports TrueType
fonts, the answer is probably no. TrueType fonts are stored on the host system, then
automatically downloaded through the printer driver whenever needed. If, however, you are
running production software on Unix, Linux, HP/UX, AIX, Pick, etc. and your software
creates reports by generating PCL output, then downloadable soft fonts may be useful.
If you need a specialized font (barcodes, OCR, MICR...) in your PCL-formatted reports, you
can install SIMM/DIMM modules in each of your printers. If you have only one or two
printers, this may be a good solution. However, if you have a larger number of printers
the cost of the SIMM/DIMM modules can add up (typically $250 to $450 per printer), and the
SIMM/DIMM you need may not be available for all of the particular brands or models of
printers you have. In this case, it would be worth taking a look at downloadable soft
fonts.
The benefits of downloading special fonts...
- Economy: Downloadable fonts cost less than hardware modules if you have
more than two printers, and they work with any brand or model of printer (PCL4 or higher),
so they will most likely work with the printers you already have.
- Flexibility: When it comes time to replace a printer, you do not lose
your investment (as you would with a SIMM/DIMM module), and you are not restricted in your
choice of a replacement printer... you can choose based on price and performance, not the
availability of a specific SIMM/DIMM.
- Reliability: If your high-capacity production printer goes down, you
can always get by in an emergency by sending print jobs to any of your other laser
printers.
Why downloadable fonts are good for barcodes...
A downloable font is one of the fastest, most flexible, precise, and economical ways to
implement barcodes on printed documents in a non-graphical operating environment (Unix,
Linux, Pick, HP/UX, AIX, etc.). A small amount of programming is required in the software
that generates the report output, but the results make it well worthwhile.
- Compact: Barcode fonts from MEC Software are typically 3K to 4K in size
and require almost no time to download once at the start of the print job.
- Fast: The PCL instructions to print a barcode typically add around 12
characters to a report. Compare this to about 65K for a typical 600dpi barcode graphic.
For example, if you are printing a batch of 200 invoices with 2 barcodes each, that's 4.8K
for fonts vs. 26M for graphics.
- Accurate: Bitmapped barcode fonts produce precise and easily-scanned
barcodes while scaleable fonts, including TrueType, introduce rounding errors that make
barcodes less that perfect (and in some cases unscannable).
- Flexible: Downloadable PCL barcode fonts are available in a wide range
of types and sizes, including custom sizes. With MEC Software's Barcode Font Generator you
can create your own fonts in any size.
More information...
