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27

I understand that either nonelectromechanical computing devices (analog) or electromechanical computing devices (digital) were ever developed by humans. That distinction is a bit off, mixing unrelated categorisation. Analogue computers can be as well mechanical, as electromechanical as well as electronic (or pneumatic or hydoponic) - similar digital ...


17

Switches and lights. Here's the panel for an IBM 650: The top row of dials are used to configure in decimal values (the IBM 650 being a decimal machine). The repeated columns of 5 lights with 2 on top indicate 1 of 10 values for each digit of the 10 digit word the IBM 650 used. The lights below that row indicate operation and address. The other dials ...


11

Does anyone know hard or time consuming it would be to achieve this? Assuming you have a modern PC with VGA out, or you can put in a graphics card with VGA out, it's not hard at all, if you know a bit about how this works. You need to look up the horizontal and vertical sync frequencies that your monitor operates with (use the documentation, or google for ...


10

From the point-of-view of someone at the time, you interacted with early computers in the usual way. From the 1930's onwards, business and some science used IBM and Remmington-Rand mechanical punched-card processing machines. You set up the specialized gear-based machines for your job (payroll, overdue accounts, super-hard math equation), punched data onto ...


8

The Apple IIc monitor (A2M4043) mentioned in the question takes a composite video signal. Some older laptops and graphics cards output composite or S-Video either directly or through a breakout cable. Otherwise, an external graphics adapter that interfaces to the PC via USB and outputs VGA is about $10-15. Once you're working in the analog domain, you have a ...


5

VGA was a huge and very bold rejection of NTSC! TLDR of this whole history section: VGA and NTSC have nothing to do with each other. VGA was a blank-sheet design that smashed NTSC limitations with extreme prejudice - and planned to never, ever, ever go back. Apple IIc monitors, like most monitors of that age, use the NTSC composite video standard in all ...


5

There have been many different kinds of I/O devices since the early years: Indicator lights (often coloquially referred to as "blinkenlights") Front panel toggle switches and pushbuttons Punched tape Punched cards Teleprinter There is some more history available at the Computer terminal Wikipedia page.


4

The Harwell Dekatron is an excellent example of this type of machine, not least because it was designed for simplicity and reliability rather than speed, and this in turn makes it easy to understand. This is a machine that operated entirely on decimal numbers, not on text. It has a few buttons on its control panel, which are essentially used to start, stop ...


4

When your memory device is literally "a screen", you can just look and see what is held in memory. (I think, but can't find a reference right now, that actually the display tube was a mirror of the actual storage tube - since the storage tube would have had a metal plate in front of it). The video in the second link is worth watching to get a glimpse of ...


4

Creating a composite signal for a monochrome monitor should be quite easy. I remember using 4 or 5 resistors to mix green, brightness, HSync and VSync from a 9-pin EGA output to construct a perfectly usable composite video signal. You will probably not find CGA or EGA adapter in 2020, but the standard 15-pin VGA looks almost as easy. The timing in VGA is ...


3

The first computer I built was a COSMAC ELF. It didn't have a keyboard or a monitor, no CLIUI/TUI/GUI. It was a full-fledged digital electronic computer. It had 8 toggle switches and a pushbutton for input and a dual 7-segment LED display for output.


3

According to the CPC schematic, the Armstrad uses a gate array to generate video, so we'd need to know how this gate array is programmed for an exact explanation. But expanding on the comment of supercat, we can do an educated guess: Assume we have an 8 bit shift register in the gate array, with a tap for bit C0 at the end, a tap for bit C1 in the middle, ...


2

I am not an expert in Amstrad CPC at all, however I can see some regularities, for example: Not grouping pixel bits in halves (like pixel 0 takes bits 7..4 and pixel 1 takes bits 3..0) allows one to use single shift register, that always shifts by 1 bit. In mode 2, it shifts 8 times for 8 pixels, in mode 1 it shifts 4 times for 4 pixels, where one pixel is ...


2

Before terminals, the most common method of interacting with large electronic tabulators, calculators, and computers (IBM mainframe, et.al.) was via punched cards for input, and line printer output for output. Some minicomputers used punched paper tape instead of punched cards. The first terminals were mechanical teletypes (ASR-33, et.al.), with a keyboard ...


2

Raspberry Pi has composite video out built in. There's a QA here which has details relevant to configuration. One of those with the appropriate adapter/cable may be the easiest way to get that old-fashioned experience you're looking for.


1

There are some solutions you could try. You can search for a monochrome VGA (actually they are multisync monitors. Search on ebay for an IBM 4707 or an IBM 8503/8504 for that 90s look. While you are at it and are lucky you could find a complete PS/2 you could use as a terminal or even try to run an older version of Linux of it (Model 90 were 486 and pentiums,...


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