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The Intecolor VHR19 terminal was introduced on the market in September, 1983, but I was able to obtain one for test only at the end of April, 1984. It was announced at an introductory price of $3995, the same as the Tektronix 4105 and the Chromatics 4200. Comparisons will be made with these terminals, and a separate section in this document on the comparison of the Tektronix and Chromatics should be read for further details. The test model I received had version 1.00 firmware, and during the test, we received version 1.10 which corrected some problems we had in alphanumeric mode. The manual is marked "***** Preliminary Version *****", so I expect that Intecolor has plans for additional features. It is reasonably well written, particularly in the section about ANSI terminal commands, and has a comprehensive index. The VHR19 features a 19-inch 60Hz color monitor and a separate box for frame buffer and power supply which connects to the monitor via four coaxial cables (red, green, blue, and sync); the frame buffer box can sit beside or under the monitor. In addition to a host RS-232C serial port on the box, there is a DMA input/output (parallel and serial) port for a video camera or printer, and an auxiliary RS-232C serial port for a trackball or digitizing tablet. Serial baud rates up to 19.2Kbaud are supported. The terminal supports pan and zoom (in steps of 1 to 8) selectable both locally and by the host. The frame buffer contains three 1024 x 1024 memory planes (giving 8 colors), each with its own NEC Graphics Display Controller chip. The terminal itself uses a 4MHz Z80A microprocessor for alphanumeric control, and displays 32 lines of 80 very readable large characters. In text mode, the foreground and background color of every character on the screen can be selected independently. The keyboard is attached with a flexible coiled cable to the frame buffer box and has a DEC VT100 layout with 23 function keys in two rows above the upper row of digit keys. The function keys can be loaded with separate sequences of up to 40 characters each for unshifted, shifted, and control states, giving 69 function keys in all. If they are not user defined, they send default three-character escape sequence "<ESC>Ox". Unfortunately, the function keys can only be locally defined, not downloaded from the host. The VHR19 emulates the Tektronix 4010/4014 monochrome graphics displays, the Intecolor graphics mode, as well as ANSI (VT100) and VT52 alphanumeric terminal modes. These four can be host selected via escape sequences, or selected locally (without loss of screen data) from a menu. All terminal settings are selectable from a color-coded menu. The input buffer size is 4K, which is large enough that I never observed any data loss at 9600 baud during the test. The graphics speed of the terminal is quite good. A test at 9600 baud drawing vectors from the upper left screen corner to every point on the right and bottom edges and then back again with color black showed that the line drawing algorithm is symmetric (a good point). In Intecolor mode with verbose commands, this test took 66 seconds; in Tektronix mode with compact vectors, it took 21 seconds. With the display size of 1024 x 768, an average vector in this test is at least 1086 pixels long, so the total number of pixels set was about 2 * (1024 + 768) * 1086 = 3.89M, giving a drawing rate of 185K pixels/sec (or 5.4 microsec/pixel) in Tektronix mode and 59K pixels/sec (or 16.9 microsec/pixel) in Intecolor mode. Rectangle fills of the 1024 x 768 screen area take about 4 sec (about 196K pixels/sec, or 5.1 microsec/pixel), and fills of screen-sized circles take about 13 sec. For comparison, it should be noted that with a microprocessor such as the Intel 8088 used in the IBM Personal Computer, even with highly optimized assembly code, it is not possible to generate arbitrary vectors faster than about 30 microsec/pixel. I was not able to get the VHR19 to use color in Tektronix 4010/4014 mode, but the factory claims that this is provided for but not yet documented. In Intecolor graphics mode, commands take the form <letter>,<digitstring>,<digitstring>,<digitstring>,... Functions available include: Pan Rectangle Zoom Circle Point Arc Relative Point Polyline Vector B-spline Curve Relative Vector Filled Polygon Concatenated Vector Filled Relative Polygon Read Position Filled Pie Slice Read Super Pixel Select Color Display Super Pixel Initialize to Default Color Super Pixel Bar Change Color Set Fill Pattern 4027 Color Definition Set Line Style Fill Screen Clear Screen Select Display Planes Write DMA Read/Write The read and write commands allow selection of a pixel in any combination of the three memory planes. The area fill patterns include a user-definable 8 x 8 bit pattern, 16 built-in patterns, and pattern numbers outside the range 0 .. 16 select unusual but predictable patterns (presumably related to their binary representation). The colors may be selected from a default set of 8 (black, red, green, yellow, blue, magenta, cyan, and white) corresponding to the CORE system basic set, or they may be individually defined in the red-green-blue model or the Tektronix 4027 hue-lightness-saturation model. Super pixels are 4 x 4 blocks with colors based on the hue-lightness-intensity model; so much data is required to define them that except for filled bars, they are of little use. The DMA Read/Write may be a way of supporting display of raster images, but insufficient detail is given to make it usable. The factory assures me that a manual describing the hardware ports is in preparation and should soon be available. Tests of rectangle and concave polygon fill were made on the VHR19 similar to the ones performed earlier on the Tektronix 4105 and Chromatics 4200. None is noticeably slower than the others when the different screen resolutions are taken into account. Concave polygons (five-pointed stars) were correctly filled. Each of these three terminals has desirable features, so that it is difficult to make a choice between them. The Tektronix 4105 has raster image display capability and a color lookup table which can be adjusted locally from a superb menu setup, but it has low resolution and neither zoom nor pan. The Chromatics 4200 is more powerful graphically than the other two, with 16 colors, zoom and pan, polygon flood fill, thick vectors, and by now should have color lookup table support (our December 1983 demonstrator did not). Its alphanumeric terminal emulation is only an ADM3A, which lacks partial erase capabilities forcing excessive blank padding (and thus slow redisplay) by a display editor, and the model we had lost characters badly above 2400 baud. The Intecolor VHR19 has double the resolution, zoom and pan, and a large screen, and an adequate supply of vector graphics primitives, though I would very much like to have these available in compact Tektronix vector format to triple the already acceptable speed. The factory claims that a compact vector format (different than the Tektronix one) will be supported in the near future. Note added 16-May-84: I liked this terminal well enough of the three in its league to buy one, though if Chromatics had resolved the alphanumeric problem, I might have chosen the 4200 instead. A big point for me is the resolution of the VHR19.