Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!sdd.hp.com!tony From: tony@sdd.hp.com (Tony Parkhurst) Newsgroups: comp.periphs.printers Subject: Re: Graphics on HP Deskjet 500 Keywords: Deskjet, HP, Graphics Message-ID: <1991Jun7.151009@sdd.hp.com> Date: 7 Jun 91 22:10:09 GMT References: Sender: news@sdd.hp.com (Usenet News) Reply-To: tony@sdd.hp.com (Tony Parkhurst) Distribution: comp Organization: Hewlett-Packard, San Diego Division Lines: 50 Nntp-Posting-Host: hpsdl116.sdd.hp.com |> Unfortunatelty, I have discovered a slight problem in the user manual: |> although it describes the printer control language itself, it leaves |> out certain critical elements to do with the format of the graphics |> command. The user manual is definately inappropriate for this. Most users will never actually do PCL programming. |> In summary: |> * What is the format for plain (ie non-compressed) data transfer? *rA Initiates graphics. *b#W Where # is the number of bytes of binary data following the 'W' which describes one row of graphics. (this command repeats for the entire graphic). *rB End raster graphics. E Finish printing page, eject page and reset printer. Note: Don't put newlines or carridge returns between these commands. |> * If the various compression schemes are known what are they? For the DeskJet and DeskJet+: Modes 0, 1 and 2 For the DeskJet 500: Modes 0, 1, 2 and 3 Mode 0 is uncompressed. Mode 1 is run length encoded. Mode 2 is a combo of modes 0 and 1 (called TIFF tag bits ?) Mode 3 is delta row encoding. I have posted a program to comp.sources.misc which reads in PCL graphics files and compresses (or decompresses) the graphics. |> * Is the technical reference manual (which HP does not supply |> with the system) really useful? Yes, indeed it has all the info you need. -- Tony Parkhurst ( tony@sdd.HP.COM ) "free people need no drug laws" -- James A. Parker