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Managing the TV-11.

The AI lab PDP-10 had a “10-11” interface with up to eight Unibuses. Each Unibus is mapped into PDP-10 memory and can be used to attach a PDP-11. Or other Unibus processors like the CONS Lisp machine, or the CHEOPS chess accelerator. The TV-11 was a PDP-11/20 attached to 10-11 Unibus number 0, suggesting it was the first to use this facility. It was shortly followed by the XGP-11, an PDP-11/10 driving the XGP printer. The TV-11 has bitmapped framebuffers, a video switch, and a keyboard scanner. It was used for raster display workstations around Tech Square.

For the TV-11 to work, it must be running, connected to the 10-11 interface, and loaded with the TV-11 software. On the PDP-10 side, ITS must be assembled with TV11P. The location TT11P controls ITS' view of the TV-11: 0 means off, -1 means running, and 1 means reinitialize.

There is a software emulator for the TV-11 and its Knight TV and keyboard hardware, called tv11 and tvcon. The tv11 talks to the PDP-10 emulator through TCP/IP; this provides the 10-11 interface. When ITS has booted, the TV-11 software must be loaded. This is done by running :STUFF TV. If the 10-11 interface works, the software will be written to the PDP-11/20 core memory. Next, ITS must be told to reinitialize its communication with the TV-11. This is done by depositing 1 to ITS location TT11P. STUFF and TT11P are normally automatically handled by the program CHANNA; RAKASH TVFIX.

The TV “console” emulator, i.e the display and keyboard, is a separate program called tvcon. It talks to tv11 through TCP/IP.

its_managing_tv11.txt · Last modified: 2020/03/16 18:42 by lars