Yet another addition, Type 19 High Speed Channels

[Bill E]

Ok, what and why? It was a 3 channel dma option used by external hardware that needed fast block transfers to/from memory, such as the drums, mag tapes, etc. This replicates it and duplicates the timing of the original. Use it for authenticity and to make bulk memory transfers easy. It has no visible control from the -1 user side, it was pure hardware. I've provided functions to let IOTs pretend they are hardware using it.

The Type 23 drum emulation is now using it.

Read about it in the original PDP-1 handbook.

In my fork, as usual.

Bill

PS - ok, I'm running out of things to add that no one is using. :) Any suggestions for more? Don't think I'm up to adding mag tapes.