In article <53CAE12D.3080404 at bitsavers.org>, Al Kossow <aek at bitsavers.org> writes: Are you saying the VT-14 has a PDP-8 inside it with the VT8-E display modules mounted inside? -- "The Direct3D Graphics Pipeline" free book <http://tinyurl.com/d3d-pipeline> The Computer Graphics Museum <http://ComputerGraphicsMuseum.org> The Terminals Wiki <http://terminals.classiccmp.org> Legalize Adulthood! (my blog) <http://LegalizeAdulthood.wordpress.com>

For the PDP-11 Qbus environment, DEC produced a VT100 with a 4 x 4 Qbus backplane inside and named it the VT103. The 4 x 4 Qbus backplane was serpentine ABAB and able to hold 4 quad cards or 8 dual cards or any compatible mixture. Unfortunately, the 5 volts was limited to 16 amps - INCLUDING what the VT100 used as well, so there was really insufficient power to a full set of cards, in particular an RQDX1 or an RQDX2. However, at one point, I did test out with a quad M8190-AB, a 4 MB quad memory card, a dual DHQ11 and a dual CQD 220M/T host adapter. So there was still one quad slot empty. I presume that a PDP-11/93 CPU card could be used instead which would have added 7 DL ports and eliminated the quad 4 MB memory card leaving TWO quad slots empty. BUT I did not have the PDP-11/93 card at the time. Of course, all of the SCSI disk drives (including a Sony SMO S-501 for backup and recovery) were powered by an additional external power supply. At this point, if I were to repeat the test, I would use AT LEAST FIVE DEC 2 GB RZ28D-E SCSI hard drives (plus the magneto optical drive for disk storage) which would certainly be substantial enough disk storage and backup for almost any PDP-11 application. I was also tempted to at least add a DLV11-J to be able to activate one of those ports for a hard copy printer (DECwriter 3) that would have used the back of the VT100 portion DB25, but there really was no point. The point of the above information is that DEC seems to have used some of the popular (at the time) terminals to be integrated as combination terminal and popular PDP (Program Data Processor - after all, they were never :-) actual computers) systems. In the case of the PDP-11, the power of the system could at least equal anything that DEC ever produced, although the options might be a bit limited. Jerome Fine

In article <CAFrGgTR=_ft5ZemGvOGcVfWcTeep5MAsJmY6aHh8tHX=hZi3NQ at mail.gmail.com>, Eric Smith <spacewar at gmail.com> writes: Not only what Eric said above, but the VT100 was designed with room for a small expansion chassis inside. The VT8-E is "a video display option for the PDP-8/E, PDP-8/F, and PDP-8/M, consists of a display monitor and three quad modules that plug into the OMNIBUS. The quad modules control the display monitor operation [...]. The display monitor comprises a CRT and its associated power supply, deflection circuits and video circuits, and a Teletype keyboard with its control logic. The monitor is contained in a desk-top enclosure." VT8-E High Speed Video Display Terminal and Control option, May, 1973 <http://manx.classiccmp.org/details.php/1,21509> This implies that the VT05 enclosure doesn't house the frame buffer (VT8-E supports graphics or alphanumerics) or the video scanout circuitry of the frame buffer, but only the high voltage circuitry and keyboard logic. Bell's "Computer Engineering" text says this about the VT14: "An interesting offshoot of the [PDP-14/30] development was the creation of a special terminal for programming, program load and observation console. This terminal consisted of a CRT and PDP-8 mounted in a portable housing." (Chapter 7, Computer Engineering) <http://manx.classiccmp.org/details.php/1,21511> So this implies that the VT14 did indeed have a PDP-8 inside it. Looking closer at the VT14 engineering drawings, I see these modules listed as inserted into the OMNIBUS assembly (pg. 12): <http://manx.classiccmp.org/details.php/1,21267> M8320 Bus Loads M8349-YE \ M8349-YE | MR8-F Reprogrammable Memory M8349 | M8349 / M8655 Terminal Control M8650 (KL8-E) Asynchronous Data Control M7443 Display VT14 Video M7441 Control Keyboard M8300 Major Registers M8310 Major Registers M8330 Timing Generator None of these appear to be the VT8-E modules: M8335 printer/keyboard control module M8336 clock and frequency divider M8337 line buffer module -- "The Direct3D Graphics Pipeline" free book <http://tinyurl.com/d3d-pipeline> The Computer Graphics Museum <http://ComputerGraphicsMuseum.org> The Terminals Wiki <http://terminals.classiccmp.org> Legalize Adulthood! (my blog) <http://LegalizeAdulthood.wordpress.com>