Hello, I’ve seen that on Wyse terminals used for library OPAC’s (online public access catalog) running Dynix.
Tommy Chang > On Mar 10, 2024, at 7:22 PM, Douglas Taylor via cctalk > <cctalk@classiccmp.org> wrote: > > I took a second look and here are the keys that were 'locked': > Set Up > Break > Del > Line INS Char > Line DEL Char > Scrn CLR Line > INS Repl > Escape > Home > All the Arrow keys, up, down, right, left > > It's a standard ASCII Wyse Keyboard > > Doug > >> On 3/10/2024 6:10 PM, Dennis Boone via cctalk wrote: >> > I thought, at first, some dirt or debris had gotten stuck there, but >> > on closer look I saw something black below the keys that seemed to be >> > stuck. I pulled a key cap off and found a U shaped piece of black >> > plastic that was put there on purpose to prevent you from depressing >> > the key. >> >> > The question came to mind; "What sort of application would be so >> > crude that you would have to prevent the user from depressing certain >> > keys?" >> >> I saw this in at least two applications: >> >> 1. The Service Merchandise chain >> (https://en.wikipedia.org/wiki/Service_Merchandise) used serial >> terminals for their in-showroom catalog ordering. Some keys were >> blocked somehow, though I never peeled up key caps to see how. :) >> I want to say that backspace was one of the blocked keys, the >> aggravation of which is probably why I remember this. >> >> 2. CLSI library systems (LIBS100 on PDP-11). Ours here had ADM-3A >> (iirc) terminals with the break key blocked, iirc, though there were >> plenty of other ways to discombobulate the thing inadvertently. It was >> also available via dialup from keyboards that were not so modified. >> >> I once heated up a paper clip to read hot and shoved it through the stem >> of a TVI-925's SEND key, which was used for block mode functions, and >> caused the terminal to vomit screen contents back to the host. Unwanted >> presses of course produced a heck of a mess. (Older versions of our >> application ran in block mode, but you could always hit ESC-S to send >> the screen, and it was unfortunately easy, at least for me, to thwack >> SEND by mistake.) >> >> De > >