Type 340 display questions

[Bill E]

As usual, more questions than answers.

The 340 was a complex beast used on multiple PDP-x systems, at least -1, -4, -6, and -7.

So, a couple of questions:

Does any existing software actually use it?

What IOTs did it use? Conflicting info, one place says 15-17, another 25-27.

25-27 overlaps the Type 33 symbol generator.

OTOH, it had its own specific symbol generator,  the Type 342, which was not a separate

set of IOTs.

Other than this conflict, it seems the Type 30/33 set could coexist on the same system.

Yes, in another fit of insanity, I'm implementing it. Much easier since I refactored the core display code. Well, relatively much easier. It has 8 different operating modes, does dma, does memory access of data following the iot instruction, changes the pc, has its own skip instructions, etc. Like I said, a complex beast.

Bill

[Norbert Landsteiner]

I think, Lars Brinkoff may know more about the 340, but probably mostly as related to PDP-6 and its interface.

Best,

Norbert