Skip to main content

Questions tagged [early-computer]

Early computers and their design, from before the standards set by the IBM S/360 (of 1964) became canon.

Filter by
Sorted by
Tagged with
12 votes
2 answers
1k views

Was there an Easter egg in the Electrologica X1 QUINIO (GO-MOKU) game?

The CWI software archive on GitHub contains the Algol-60 source code for a gomoku-like game. It is runnable with your favorite Algol-60 compiler and a little elbow grease (in particular, taking the ...
Leo B.'s user avatar
  • 20.7k
4 votes
1 answer
280 views

Why does the Z22 have a read-only shadow of the return address location?

For some context to this question see Raffzahn's excellent question and answer How were Zuse Z22 Instructions Encoded?. The Z22 treats the first few locations of its address space in a particular way:...
Omar and Lorraine's user avatar
11 votes
6 answers
3k views

What made the ENIAC "programmable"?

The ENIAC was the first programmable, electronic, general-purpose digital computer. However, it was programmed by "rewiring", and this is what I do not understand. When we say "...
Noob_Guy's user avatar
  • 713
15 votes
4 answers
6k views

How could early computers perform data operations before John von Neumann proposed the concept of ALU?

According to Wikipedia, John von Neumann proposed the Arithmetic and Logic Unit concept in 1945. Mathematician John von Neumann proposed the ALU concept in 1945 in a report on the foundations for a ...
Noob_Guy's user avatar
  • 713
22 votes
1 answer
527 views

Looking for help understanding a 'Reciproot' routine on the Manchester Mark I (1951)

I'm hoping to understand a routine written for the Manchester Mark I [NOTE: a comment from Raffzahn suggests this may be the Ferranti (wikipedia link) and not the Manchester Mark I] which computes ...
Adam Hyland's user avatar
  • 1,063
10 votes
1 answer
1k views

What did Shin Nihon Kikaku (SNK) originally manufacture in 1973?

The company SNK was originally Shin Nihon Kikaku, founded in 1973. What did Shin Nihon Kikaku originally manufacture in 1973? I would assume some sort of primitive computers or calculators, but ...
Hitek's user avatar
  • 935
9 votes
2 answers
1k views

Why was ones-complement integers implemented? [duplicate]

Wikipedia’s article on ones’ complement mentions large brands using it in their hardware for integer arithmetic into the late 1980s. This is surely for backwards compatibility? According to the ...
Captain Giraffe's user avatar
14 votes
1 answer
527 views

Source For V2/A4 Missile Analog Guidance Computer Schematic?

As a retro computing hobby project, I'm researching Helmut Hoeltzer's (Hölzer's) work on the Mischgerät analog guidance computer for the V2/A4 ballistic missile, with the goal of validating a ...
cmholm's user avatar
  • 351
7 votes
1 answer
380 views

When was a compiler first used to generate code to be placed in ROM?

In the early days of compilers, it was expected that programs would generally be stored in an inexpensive medium (such as punched cards or magnetic tape) when not in use. Although it was possible to ...
supercat's user avatar
  • 39.2k
13 votes
3 answers
1k views

How did the Burroughs B5000/B5500 provide hardware support for implementing Algol's call-by-name?

According to a 2019 presentation about Burroughs Extended Algol, the Burroughs B5000 and B5500 (and presumably their descendants) had “Hardware support for Call-by-Name (‘thunks’)”. It goes on to say ...
texdr.aft's user avatar
  • 3,730
6 votes
2 answers
1k views

Were any decimal-based computers capable of handling text?

Many of the earliest computers stored and manipulated numbers in various decimal codings rather than in pure binary. Examples include the Mark I and ENIAC, as well as some UNIVAC and IBM models. ...
DrSheldon's user avatar
  • 16.6k
2 votes
1 answer
253 views

What's with the TX-0 punchtape instructions?

The TX-0 has a class of instructions very similar to the PDP-style microprogrammed, operation instructions. Fill the opcode field with all ones, and then select which microoperations you want to ...
Omar and Lorraine's user avatar
1 vote
1 answer
182 views

What kinds of input/output devices could the Electrologica X1 interface with (simultaneously)?

Here is a brief survey of the literature that I know of/have access to: The most complete description of the X1 that I am aware of is given in Dijkstra's 1959 PHD thesis, which describes in detail ...
texdr.aft's user avatar
  • 3,730
5 votes
5 answers
664 views

Are there any good resources on emulating/simulating early computing input/output?

Note: I hope this question is on topic. I'm not sure where else to put it. There are several tutorials available online for writing emulators/simulators. Unfortunately they all seem to focus on ...
texdr.aft's user avatar
  • 3,730
1 vote
1 answer
197 views

Why didn't the Whirlwind I use a high persistence crt or something?

Why didn't the Whirlwind I use a high persistence crt or something ? On this video Whirlwind I at 1:48, you can see the text being diplayed, it is only very briefly visible, apparently they would take ...
mnml's user avatar
  • 450
2 votes
1 answer
339 views

Who built the first electric/electronic adder?

The first electricity-based adder presumably used relays. (The electromechanical relay was invented for the electrochemical telegraph for repeaters in 1831 by Joseph Henry (1797-1878). I can't figure ...
vy32's user avatar
  • 283
5 votes
2 answers
466 views

Data length module of 3.2^n confusion in IBM system/360 architecture

I'm currently reading about the IBM system/360 architecture and there's a part that has me very confused: The decision on basic format (which affected character size, word size, instruction field, ...
KetDog's user avatar
  • 405
6 votes
1 answer
1k views

Did this analogue computer from 1960 really have Internet?

If you zoom in this image, to the leftmost, white "cell" in the middle "row" of the machine, it says, in the bottom, "INT NET": https://upload.wikimedia.org/wikipedia/commons/c/c6/PACE-TR-...
Josian's user avatar
  • 97
22 votes
8 answers
4k views

Do the holes in Jacquard loom punched cards represent input data or program code?

I think they represent data because I feel it is a mechanical machine which is fully configured and the holes decide only that the thread related to each hole must be moved or not. Thus the holes ...
user42757's user avatar
  • 379
2 votes
2 answers
510 views

What early computers were only able to print numbers?

According to this paper (translation), one of the early soviet machines, M-1, was only able to print decimal, and not alphabetical numbers. Which other early electronic stored program computers (i.e. ...
lvd's user avatar
  • 11.4k
4 votes
4 answers
515 views

What is the first (say early) use of switches (mechanical or electromechanical) for sake of processing (like automatic motor control)simple data?

Switches are intended for just turning ON or OFF the power supply by either closing or opening the circuit. I often wonder how does mankind got idea to use these switch for sake of processing (simple ...
user42757's user avatar
  • 379
3 votes
1 answer
331 views

Was UCLA's 1948 Mechanical Computer programmable, or merely a calculator?

We define programmable machines as those that can do: sequence selection, and iteration ie the Turing Model of Computing. Here we see the UCLA's 1948 Mechanical Computer performing a calculation. ...
hawkeye's user avatar
  • 3,067
16 votes
1 answer
3k views

Do we know the problems the University of Manchester's Transistor Computer was intended to solve?

We can see that the University of Manchester built a transistor computer in 1952. This appears to have been the first transistor computer. We can see that the design was used in the Metrovick 950. ...
hawkeye's user avatar
  • 3,067
11 votes
3 answers
802 views

What is the difference between CTSS and ITS?

I learned from the history of Multics that in the early days of computers, Time Sharing System (TSS) was used at MIT, and then Compatible Time Sharing System (CTSS) was developed in 1961, also at MIT. ...
Pandya's user avatar
  • 683
5 votes
2 answers
629 views

IBM 650 - how many logic gates?

How many logic gates did the IBM 650 have? I'm used to measuring the complexity of a CPU by transistor count, but the 650 was a vacuum tube machine; the number of tubes would also be an interesting ...
rwallace's user avatar
  • 63.8k
52 votes
4 answers
7k views

Why did the IBM 650 use bi-quinary?

The IBM 650, announced in 1953, was the world's first mass-produced computer. It represented numbers in decimal, which is understandable, both because it needed to work with exact money amounts, and ...
rwallace's user avatar
  • 63.8k
17 votes
1 answer
1k views

How were Zuse Z22 Instructions Encoded?

The title says it all: How to En-/Decode Z22/Z23 Instructions? (History and Linkage: The question was raised by Wilson in a comment on my answer to his question "Why are PDP-7-style microprogrammed ...
Raffzahn's user avatar
  • 236k
6 votes
3 answers
287 views

How does the floating point conversion in Zuse's machines work?

Can someone please help me understand the floating point to readable decimal conversion algorithms of the Z1 and Z3? There is a patent in German containing all the information but I can't speak German....
Yin Xuan Yang's user avatar
29 votes
3 answers
4k views

Why does an instruction include the address of the next instruction on the IBM 650?

The IBM 650 seems to be a load-store machine. One advantage of a load-store machine is that the instruction can be shorter because there's less pressure to pack more information into it. But the IBM ...
Omar and Lorraine's user avatar
12 votes
3 answers
1k views

What is the instruction set of the Z4?

I am able to find a few instructions, such as: Fin (presumably "Fine", as in the end of a musical score, ends a program), Fin', (a conditional Fin), St (possibly "Start" -- the need for this is ...
Omar and Lorraine's user avatar