MattisLind
Veteran Member
Now that Anders and I have got this big pile of DECtapes (or LINCtapes) each it would be very useful to recover any software from these. Getting the PDP-9 to run is a major task. And the PDP-12 is a five year plan.
I thought it would be useful to have a stand alone TU55 controller that one could connect to a PC via USB. And it would be a new interesting project now that my PC04 reader project is more or less finalized (it works fine with a PC but I like to test it with a 11/03 and a M8028 card and load some actual software).
From my understanding the TU55 is a fairly simple device. SELECT lines, FWD, STOP, REWIND, GO and a few other digital signals. All these signals on one single board. Then the actual R/W head data on a dual board. The analog R/W head data is feed into either a G882 or G888 module. The G882 seems to be just a discrete non-adjustable version of the G888. Not being an analog expert, but I think it should be possible to replace the old op-amps / discrete transistors with some modern simple op-amp and also a circuit that prolongs the pulse width.
As far as see it the period of the timing track is quite low and would probably be possible to handle with an AtMega chip.
So what do you think? Has somebody already done this? Am I missing some severe problems related to the TU55 and the format of the tape? Any input is appreciated!
I thought it would be useful to have a stand alone TU55 controller that one could connect to a PC via USB. And it would be a new interesting project now that my PC04 reader project is more or less finalized (it works fine with a PC but I like to test it with a 11/03 and a M8028 card and load some actual software).
From my understanding the TU55 is a fairly simple device. SELECT lines, FWD, STOP, REWIND, GO and a few other digital signals. All these signals on one single board. Then the actual R/W head data on a dual board. The analog R/W head data is feed into either a G882 or G888 module. The G882 seems to be just a discrete non-adjustable version of the G888. Not being an analog expert, but I think it should be possible to replace the old op-amps / discrete transistors with some modern simple op-amp and also a circuit that prolongs the pulse width.
As far as see it the period of the timing track is quite low and would probably be possible to handle with an AtMega chip.
So what do you think? Has somebody already done this? Am I missing some severe problems related to the TU55 and the format of the tape? Any input is appreciated!