bbb@kuhub.cc.ukans.edu (05/02/91)
Dear Net-ers: Earlier this week got my Orchid PRO- DESIGNER-II (Along with a Sony-1304-- GREAT COMBO) and just today got my Tseng Lab Inc. (TLI) ET-4000 controller data book. While checking out the specs on the 4000-chip, my eyes bugged as I saw that it is (in theory anyway) capable of producing 65535 colors on screen using 2 bytes to produce a pixel. Unfortunately there is little additional information in the TLI manual. (at least as far as I can decipher.) Sooooo, the question. Can any of you graphic gurus out there give me any help on using this 'mode' of the chip? IT IS NOT one of the standard INT-10 functions, and I'm assuming I'll have to 'poke' it in my self. Will the Pro-II even allow it work? Is it too much trouble to dink with? E-Mail welcome. Thanks in advance. BB
graeme@labtam.labtam.oz (Graeme Gill) (05/05/91)
In article <1991May2.001518.30298@kuhub.cc.ukans.edu>, bbb@kuhub.cc.ukans.edu writes: > Dear Net-ers: > > ... and just today got my > Tseng Lab Inc. (TLI) ET-4000 controller > data book. > > While checking out the specs on the > 4000-chip, my eyes bugged as I saw that > it is (in theory anyway) capable of > producing 65535 colors on screen using 2 > bytes to produce a pixel. As I understand it, this is some sort of HAM (Hold And Modify) scheme where the chip is put in a special mode, and certain colour values are reserved as "instructions" to interpolation hardware to generate colours between two of the available palette colours. This basically means that it is great for specially written CAD packages that know how to use it for ant-aliased lines etc., but it is not much good for general purpose use. (ie. If you want to be able to set any pixel to any one of 65535 colours). It also has a dynamic palette feature, that allows the palette to be re-programmed on the fly. One only has to look at the difficulty people have had in using the Amiga HAM mode to wonder how usefull all this stuff is. Graeme Gill Labtam Australia
roell@informatik.tu-muenchen.de (Thomas Roell) (05/06/91)
>> While checking out the specs on the >> 4000-chip, my eyes bugged as I saw that >> it is (in theory anyway) capable of >> producing 65535 colors on screen using 2 >> bytes to produce a pixel. > > As I understand it, this is some sort of HAM (Hold And Modify) scheme >where the chip is put in a special mode, and certain colour values are reserved >as "instructions" to interpolation hardware to generate colours between two >of the available palette colours. No, you are dead wrong. The Et4000 is capable of sequencing 16bit pixels. There is just the normal timing, except per dot-clock cycle two bytes are send to the CLUT. Some CLUTs (or call them RAMDAC) can use this to drive their DACs directly. For example the Sierra RAMDAC uses 5 bits (of these 16) for each primary color and can thus display 32768 colors simultaneousely. - Thomas -- _______________________________________________________________________________ E-Mail (domain): roell@lan.informatik.tu-muenchen.de UUCP (if above fails): roell@tumult.{uucp | informatik.tu-muenchen.de} famous last words: "diskspace - the final frontier..."
eli@smectos.gang.umass.edu (Eli Brandt) (05/07/91)
In article <10497@labtam.labtam.oz> graeme@labtam.labtam.oz (Graeme Gill) writes: >In article <1991May2.001518.30298@kuhub.cc.ukans.edu>, bbb@kuhub.cc.ukans.edu writes: >> Dear Net-ers: >> >> ... and just today got my >> Tseng Lab Inc. (TLI) ET-4000 controller >> data book. >> >> While checking out the specs on the >> 4000-chip, my eyes bugged as I saw that >> it is (in theory anyway) capable of >> producing 65535 colors on screen using 2 >> bytes to produce a pixel. > > As I understand it, this is some sort of HAM (Hold And Modify) scheme >where the chip is put in a special mode, and certain colour values are reserved >as "instructions" to interpolation hardware to generate colours between two >of the available palette colours. This basically means that it is great for >specially written CAD packages that know how to use it for ant-aliased lines >etc., but it is not much good for general purpose use. (ie. If you want to >be able to set any pixel to any one of 65535 colours). It also has a dynamic >palette feature, that allows the palette to be re-programmed on the fly. One >only has to look at the difficulty people have had in using the Amiga HAM mode >to wonder how usefull all this stuff is. > > Graeme Gill > Labtam Australia I think you're thinking of Edsun's CEG DAC. (Continuous Edge Generat*) The CEG is basically a plug-in replacement for the standard VGA DAC, in that it uses the same video-memory organization as VGA/Super VGA. ie, max 1 byte per pixel. Tseng's ET-4000 is, I believe, a true 16-bit-color device, using two bytes for each pixel. The CEG does indeed use some rather baroque HAMmy modes to do its smoothing; you embed special pixel sequences directly into the bitmap. Please note that I've never seen either of these, and I know virtually nothing about Tseng's chipset. Except that I *want* one. / Eli Brandt eli@smectos.gang.umass.edu 32@4351 WWIV \ \ Mentally insert disclaimers Mentally insert quote /
daly@ecs.umass.edu (Bryon Daly, ECE dept, UMass, Amherst) (05/07/91)
In article <30124@dime.cs.umass.edu>, eli@smectos.gang.umass.edu (Eli Brandt) writes: > In article <10497@labtam.labtam.oz> graeme@labtam.labtam.oz (Graeme Gill) writes: >>In article <1991May2.001518.30298@kuhub.cc.ukans.edu>, bbb@kuhub.cc.ukans.edu writes: >>> Dear Net-ers: >>> >>> ... and just today got my >>> Tseng Lab Inc. (TLI) ET-4000 controller >>> data book. >>> >>> While checking out the specs on the >>> 4000-chip, my eyes bugged as I saw that >>> it is (in theory anyway) capable of >>> producing 65535 colors on screen using 2 >>> bytes to produce a pixel. >> >> As I understand it, this is some sort of HAM (Hold And Modify) scheme >>where the chip is put in a special mode, and certain colour values are reserved >>as "instructions" to interpolation hardware to generate colours between two >>of the available palette colours. This basically means that it is great for >>specially written CAD packages that know how to use it for ant-aliased lines >>etc., but it is not much good for general purpose use. (ie. If you want to >>be able to set any pixel to any one of 65535 colours). It also has a dynamic >>palette feature, that allows the palette to be re-programmed on the fly. One >>only has to look at the difficulty people have had in using the Amiga HAM mode >>to wonder how usefull all this stuff is. >> >> Graeme Gill >> Labtam Australia > > I think you're thinking of Edsun's CEG DAC. (Continuous Edge Generat*) > The CEG is basically a plug-in replacement for the standard VGA DAC, in that > it uses the same video-memory organization as VGA/Super VGA. ie, max 1 byte > per pixel. Tseng's ET-4000 is, I believe, a true 16-bit-color device, using > two bytes for each pixel. The CEG does indeed use some rather baroque > HAMmy modes to do its smoothing; you embed special pixel sequences directly > into the bitmap. Please note that I've never seen either of these, and > I know virtually nothing about Tseng's chipset. Except that I *want* one. > > / Eli Brandt eli@smectos.gang.umass.edu 32@4351 WWIV \ > \ Mentally insert disclaimers Mentally insert quote / > > I just heard that Diamond is releasing two new video boards based on the Tseng ET4000 chipset. The first is the Edsun CEG-based one. (CEG=Continuous Edge Graphics). The Edsun chip is more than a HAM scheme, and is actually a DSP chip, from what I've heard, and does 64K colors, but not in a user programmable way: You won't have 16-bit color to program. Instead, the chip automagically interpolates colors along edges, to eliminate aliasing, etc. (Special programming is reqired, though!). The Edsun chip is also a direct replacement for the RAM DAC that is socketed in many current SVGA cards, but the maximum resolution it handles is 800x600, and you would need drivers to take advantage of its capabilities. Diamond claims it's card will do its stuff at 1024x768, and they seem willing to upgrade current SpeedStar owners (like me! :) ). The other board is called the Hi-Color, and they say it does 32K colors, for real. (15-bit color). The price I saw on this one was $595 (from their BBS). I think max res was 640x480 at that number of colors, but I remember no too much else about it. -Bryon Daly daly@ecs.umass.edu
bdb@becker.UUCP (Bruce D. Becker) (05/09/91)
In article <10497@labtam.labtam.oz> graeme@labtam.labtam.oz (Graeme Gill) writes: >In article <1991May2.001518.30298@kuhub.cc.ukans.edu>, bbb@kuhub.cc.ukans.edu writes: >> Dear Net-ers: >> >> ... and just today got my >> Tseng Lab Inc. (TLI) ET-4000 controller >> data book. >> >> While checking out the specs on the >> 4000-chip, my eyes bugged as I saw that >> it is (in theory anyway) capable of >> producing 65535 colors on screen using 2 >> bytes to produce a pixel. > > As I understand it, this is some sort of HAM (Hold And Modify) scheme >where the chip is put in a special mode, and certain colour values are reserved >as "instructions" to interpolation hardware to generate colours between two >of the available palette colours. This basically means that it is great for >specially written CAD packages that know how to use it for ant-aliased lines >etc., but it is not much good for general purpose use. (ie. If you want to >be able to set any pixel to any one of 65535 colours). It also has a dynamic >palette feature, that allows the palette to be re-programmed on the fly. One >only has to look at the difficulty people have had in using the Amiga HAM mode >to wonder how usefull all this stuff is. BBBRRRRZZZZZAAAAKKKK!!! ...Wrong answer... 2 bytes per pixel == 65536 colors, therefore no interpolation required. The Amiga HAM mode works with effectively 6 bits/pixel (in bitplane layout), but achieves 4096 (12 bits) colors via special coding of the last 2 bits to indicate whether the first 4 bits are 1 of 16 colors from the palette, or else a modification of either the red, green, or blue output values only. The implications of this is that it may take up to 2 intermediate changes to get from one color to the next (since only one of R, G, B is changed at a time), so the order of changes can have an effect on the visual appearance. Because the human visual system is relatively insensitive to hue detail (as opposed to luminance detail), adroit programming can produce a very satisfactory result; less skilled implementations seem to show significant color fringing, however... -- ,u, Bruce Becker Toronto, Ontario a /i/ Internet: bdb@becker.UUCP, bruce@gpu.utcs.toronto.edu `\o\-e UUCP: ...!utai!mnetor!becker!bdb _< /_ "It's the death of the net as we know it (and I feel fine)" - R.A.M.
graeme@labtam.labtam.oz (Graeme Gill) (05/09/91)
In article <1991May6.114625.6444@Informatik.TU-Muenchen.DE>, roell@informatik.tu-muenchen.de (Thomas Roell) writes: > >> While checking out the specs on the 4000-chip, my eyes bugged as I saw > >> that it is (in theory anyway) capable of producing 65535 colors on > >> screen using 2 bytes to produce a pixel. > > > > As I understand it, this is some sort of HAM (Hold And Modify) scheme > >where the chip is put in a special mode, and certain colour values are reserved > >as "instructions" to interpolation hardware to generate colours between two > >of the available palette colours. > > No, you are dead wrong. The Et4000 is capable of sequencing 16bit pixels. > There is just the normal timing, except per dot-clock cycle two bytes are send > to the CLUT. Some CLUTs (or call them RAMDAC) can use this to drive their > DACs directly. For example the Sierra RAMDAC uses 5 bits (of these 16) for > each primary color and can thus display 32768 colors simultaneousely. I think I was confusing two of the newly released RAMDAC chips here. The Et4000 controller chip, which (as you say) seems capable of providing 16 bits per clock into a RAMDAC, gives 32768 colours simultaneously when combined with a suitable RAMDAC (ie. the Sierra SC11482). I was confused because the DEFINICON RACE 1024 VGA card I have seen combines the Et4000 with a Edsun Labs EL171CEG RAMDAC, meaning that the 16 bit mode of the Et4000 cannot be used, but the Edsun RAMDAC provides the HAM type anti-aliasing mode I described above instead. The only trouble with the 16 bit/pixel mode is the data rate needed at TTL voltage levels. At 100Mhz the multiplexing up to this rate becomes a difficult problem, and the best solution is to do it inside the RAMDAC (ie BT549, IMS G180 etc.), rather than having these high speed signals go accross the PCB. Graeme Gill Labtam Australia