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IBM 4701-2 branch controller, software needed


May 24, 2019
Madrid, Spain
Hi, this is my little IBM 4700 Finance Communication System project. I have so far a restored 4704 terminal with the matching monitor and a 4701-2 branch controller that provides the local loop where the terminal should be connected.


So far I have both pieces working and I managed to get all the pinouts for the missing connection cables. I've also made a converter to be able to use any ps2 keyboard with the terminal. But sadly I don't have any software to IPL the controller. This machine needs an 8'' install diskette that is used to configure and diagnose it and to generate boot diskettes. The controller has no functionality at all without the boot media.

I publish this in the hope that someone that finds a suitable install diskette in the future could see it and contact with me.

If I'm able to IPL the controller, I hope I can use it to reverse engineer the local loop protocol and maybe make a replacement controller to be able to connect the terminal to a modern system.

The install diskettes are not to be confused with the 5 1/4 media for the later 4702 branch controller, the media for this controller is an older 8-inch Diskette.

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