Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!uakari.primate.wisc.edu!dogie.macc.wisc.edu!uwvax!per2!dag From: dag@per2.UUCP (Daniel A. Glasser) Newsgroups: comp.sys.atari.st Subject: SLM804 from emulators... Where the problem might lie. Keywords: SLM804, Spectre128, SpectreGCR, PC Ditto, PC Speed, Emulators Message-ID: <880@per2.UUCP> Date: 29 Sep 89 20:05:02 GMT Organization: Persoft Inc., Madison, WI Lines: 57 Some people have gotten really angry over the lack of SLM804 support in the various emulators running on the ST. Although I can simpathize with these people, I must take exception to the accusations that they are making about the developers of these emulators. The SLM804 is not a simple laser printer with its own imaging engine and some sort of byte serial interface to the computer. Support of the printer requires the use of an in memory bitmap large enough to contain every pixel imaged on the page (actually, with double buffering and async programming, the in memory bitmap can be smaller, but it is very difficult to program the ST in that manner.) This bitmap is then shipped to the printer via the DMA port. 300dpi on an 8.5" x 11" page with an active area of 8" x 10.5" requires 2400 x 3150 pixels, or 300 bytes x 3150 scans, or 945,000 bytes. In addition, this in-memory bitmap must be written to with text and graphics properly scaled to the output device. Postscript output requires a postscript interpreter, HP LaserJet output requires an HP PDL interpreter/emulator, etc. These interpreters and emulators take a lot of time and effort to write, are hard to debug, and require considerable memory for internal font and format storage beyond the page bitmap. The emulators do not run under or along with TOS. These programs must either run as part of the emulator itself or under the emulator. Add to that that the Atari DMA channel is very tricky to get right, and the problem gets a little worse. Add to that that this support must be transparent to the application running under the emulator, so it must behave as a common device in whatever environment is being emulated. David Small and the people at AG would probably be willing to integrate improved SLM804 support if someone were to offer them the required code at a reasonable price in a useable form. The support would probably be limited to those machines with at least 2, and probably 4, megabytes. Make whatever criterion you wish for your software selection. Tell the world about those choices that you make. State a desire for features in products that you find unusable because of the lack of those features. Please don't keep whining about those "missing" features which were never promised by the developers in the first place. Would it be better if the product were delayed by the additional months/years that it might take for a single programmer or a small team to add those features which could only be used by a small minority of what already is a small market? Maybe someone could develop a program that runs under MAC-OS specific to the ST which would do a 300dpi imagewriter (or DeskWriter) emulation on an SLM804 and sell this as a separate item. If we, as a user community, could have a little more understanding of the technology that we demand and those who attempt to provide us with it, morale (which is VERY important in this business) would be much better. -- _____________________________________________________________________________ Daniel A. Glasser One of those things that goes uwvax!per2!dag "BUMP!!!(ouch)" in the night. ---Persoft, Inc.---------465 Science Drive-------Madison, WI 53711-----------