Questions tagged [pdp-7]
For questions about the DEC PDP-7 minicomputer.
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How to read/write word from DECtape on SIMH?
I am learning programming assembly for PDP-4 using SINH simulator. I stuck at understanding how tape drives work. I want to read one word from DECtape 550 unit 1 but I don't know how. I'm learning PDP ...
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What does this image in Space Travel represent?
I was touching up the Space Travel article on the Wiki and realized no one had answered a question I posted some time ago. I suspect someone here knows the answer.
This image is used in the infobox to ...
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Null-terminated strings on the PDP-7?
I came across a post that states that Unix uses null-terminated strings, ASCIZ, because it was a feature of the PDP-7. This triggered my reading on the CIS instructions in the PDP-11, but these were ...
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Why do the later 18 bit PDPs include both ones' and two's complement?
The PDP-1 is a ones' complement machine, and does some checks to make sure you (almost) never get negative zero. I'm struggling to think why anyone would want ones' complement arithmetic, but it was ...
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Is it possible to get a pdp7 [closed]
Is it possible to get an original DEC pdp-7, if so how much would it be? I've looked around the internet, but I'm not finding anything.
user11220
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Why was UNIX never backported to the PDP-7?
Originally, UNIX was written in PDP-7 assembly, and then in PDP-11 assembly, but then when UNIX V4 began to be re-written in C in 1973 and was run mostly on the PDP-11.
So far as I can tell, there ...
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What is the instruction set of the PDP-7?
The PDP-7 was a bookshelf-sized "minicomputer", with keyboard, magnetic and paper tape and printer I/O. According to Wikipedia, the first version of UNIX (then named Unics) was programmed in assembly ...
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