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1
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0answers
98 views

Early multifunction laser printer with a fixed scanning head?

I was working for a Hungarian magazine in the early 90s which had the most curious device: a laser printer which had a pass through scanner on top ie you laid down a page and it dragged it under a ...
20
votes
17answers
4k views

Were any IBM mainframes ever run multiuser?

Now of course there is a sense in which they were – some mainframe installations supported thousands of users! But there is a distinction. Consider the familiar fixture in so many 80s computer science ...
5
votes
1answer
144 views

What was the first database to start compressing in situ?

The obvious way for a database to store data is with each record in a contiguous chunk, and each field having a fixed size and offset in the record. Joel Spolsky praises that way of doing things: ...
4
votes
1answer
251 views

How did the DEC RP06 respond to unscheduled power off?

The DEC RP06 disk drive was a remarkable piece of hardware. It seems to have been the last generation of drives that used rigid magnetic disks in removable packs, before their replacement by '...
20
votes
5answers
5k views

Why did mainframes have big conspicuous power-off buttons?

Some fascinating stories in this discussion thread. It starts with discussion about computers overheating, but about halfway through the thread, it switches to discussion of mainframe installations in ...
3
votes
1answer
191 views

PC Task performance

What sort of performance I can expect from PC Task 4.4 on Amiga 500 + 030 50MHz MMU, 64MB RAM? Would it be possible to run Windows 3.11 / 95 and have any real use from it?
3
votes
0answers
144 views

Why did Gran Trak 10 cost so much?

In 1974, Atari released a driving game called Gran Trak 10. The development prototypes had used real car steering wheels and pedals, but it was realized these were too expensive, so they were changed ...
27
votes
4answers
5k views

Why did MacOS Classic choose the colon as a path separator?

I mean, all other OSs that I know of use some form of slash as a path separator, so why did Apple choose the colon?
5
votes
3answers
1k views

How was it possible to run IBM mainframe software in emulation on HP?

... At least, without getting sued into the ground? According to one of the answers to What was the most critical supporting software for COBOL on IBM mainframes? We installed a new HP replacing an ...
20
votes
7answers
3k views

What was the most critical supporting software for COBOL on IBM mainframes?

Over the past half-century, one of the largest trends in the computer industry has been the replacement of mainframes by microcomputers. Not total by any means – there are still many mainframes in ...
7
votes
2answers
478 views

Labels in cc65 inline assembler with #define macro

In general, it is possible to use inline assembler statements within C macros, for example #define toscreencode(C) (__AX__ = (C), \ asm("cmp #$60"),\ ...
1
vote
0answers
155 views

Internet services that are still compatible with devices (phones/pdas from 2000-2007) [closed]

Though I can identify some technologies like following, I would like to know which ones will surely fail and which ones are worth to test on my old Palm, Symbian, WindowsCE,... Web Issues with ...
5
votes
2answers
543 views

Sony PVM Connections / Composite Signale

I am trying to learn more about different video formats. I have a SONY PVM9044QM and want to understand the different connection options. So I understand, that Y/C equals S-Video input. But what does ...
1
vote
1answer
241 views

How to remove Virus:DOS/V_Sign from a DOS 6.22 system

Fresh install of dos 6.22, unfortunately there appears to be a virus in MBR, each time I get Virus:DOS/V_Sign when re-using floppy from this machine. I can't connect HDD to modern PC, any idea how I ...
9
votes
3answers
2k views

Why did decimal arithmetic slow down VisiCalc?

There is an excellent article about VisiCalc that goes into all the details about what happened and why, highly recommended if you are interested in that part of computing history. I was reading this ...
4
votes
3answers
2k views

8086 duration of program

I have the following assembly code for 8086 MOV AL, [BX] OUT DX, AL The bus clock frequency is 1MHz. Access to memory is done without WAIT, and to I/O with one WAIT tick. How I can calculate the ...
1
vote
0answers
110 views

Failure modes of old motherboards vs new motherboards [closed]

I have a question regarding the difference in common failure modes between an older motherboard such as the ABIT BP6, and a new motherboard such as what you might find in an Intel NUC. What is a ...
8
votes
2answers
538 views

Origin of Ctrl-Alt-Delete key combination to reset

The Ctrl + Alt + Del key combination to reset is known to me to work on older PC/MS-DOS PCs, some versions of Atari TOS, on runlevel 3 / multiuser.tager Linuxes (it can be disabled). The older of ...
13
votes
2answers
927 views

How were 4-digit IC part numbers assigned?

It seems that integrated circuits of the 1970s tended to have 4-digit part numbers. This includes not only the ones that came to be well-known like CPUs (Intel 4004, 8008, 8080, 8085, 8086, 8088, ...
0
votes
0answers
66 views

Amstrad CPC 6128 - Key cap spring missing

Of course the unthinkable happened and I lost one cap key spring while cleaning the keyboard. I am still searching but assuming all things went south, what would be the best solution to replace them? ...
5
votes
1answer
248 views

How to identify the filesystem for an old SCSI drive?

Back in the day, SCSI was the way to go. I remember my high school having a single 5Mb Sider hdd connected to an Apple //e - which seemed awesome after endlessly swapping floppies. Not long after, I ...
3
votes
2answers
473 views

How did wave soldering work? [closed]

While it is not used as much nowadays, wave soldering was a big advance in the productivity of manufacturing electronics, compared to soldering all the components by hand. It consists of placing all ...
4
votes
4answers
376 views

Using a GSM (2G) cellphone as a modem to send code

I am quite a newbie to retrocomputing, and I don't know if such a question should be asked here. But I hope maybe some of you could help me. I started reflecting on ways to send data without the ...
3
votes
1answer
94 views

Amstrad CPC 6128 - Bench Power Supply Connection Setup

I am definitely at the very beginning of my refurb-journey and learning every step now on the way ... I struggle with the following: I saw a video by Noel's Retrolab where he troubleshooted a CPC. He ...
2
votes
3answers
194 views

First time using an Amstrad CPC 6128 Disc Drive [duplicate]

I recently got my first Amstrad CPC and started refurbishing it. Now I wonder, I saw a video, on someone using the RPM test tool for the Amstrad. I found the download online, but this question might ...
4
votes
2answers
204 views

Were there “higher level programming” macro packages for the IBM Macro Assembler?

The IBM/360 Macro Assembly language was quite powerful, allowing non-trivial compile-time string manipulation. Did macro packages exist which would facilitate programming at a (slightly) higher level, ...
4
votes
2answers
353 views

Was the ProDOS beep part of the kernel or just a commonly duplicated piece of code?

On the Apple II, system beeps were typically just the 'Control-G' beep noise. However, many ProDOS-based applications from Apple Computer abandoned the firmware-based beep routine and instead used a ...
7
votes
3answers
267 views

How does Symphonie Pro actually work?

I just happened upon this video: https://www.youtube.com/watch?v=6tNizdyx-DE It's a selection of Amiga music produced using a program I've never heard of before: "Symphonie Pro". Does ...
8
votes
1answer
295 views

What was IBM’s early attempt at an OS/2 office suite?

I definitely remember that sometime after OS/2 was introduced - while it was still in its very early days - after the breakup from Microsoft, long before Warp - IBM announced with great fanfare a ...
19
votes
8answers
4k views

Why user-assembled kits?

Many early computers were sold as self-assembly kits (you get a box of parts and an instruction leaflet and have to solder them together yourself). For example, the Altair was priced at $439 kit, $621 ...
12
votes
4answers
903 views

Did the Commodore datasette interface provide greater reliability?

Cassette, being cheaper than a floppy disk drive, was a popular storage medium in the 8-bit era. Some computers such as the Sinclair Spectrum, just provided a port to plug in an existing cassette deck....
9
votes
2answers
696 views

Did any 8-bit CPUs use dynamic memory for registers?

According to https://jamiestarling.com/project-8088-the-8088-cpu-pinout/ One thing to note – the 8088 registers are made from dynamic memory cells – they have to be refreshed. The minimum clock speed ...
3
votes
2answers
266 views

Could the 6502 have worked with an Altair-style front panel?

I have fond memories of programming the 6502, though I never did any hardware hacking with it. I notice that the Altair, with its iconic front panel, was based on the Intel 8080, and from then on, ...
5
votes
1answer
168 views

Menu in Octapolis

I have been retrogaming with Octapolis on an emulated Commodore 64. Starting up the game presents a menu offering a choice between one or two players, and between music and sound effects. But I don't ...
6
votes
3answers
974 views

Why does -z and -n exist in most shells and /bin/test?

The test command on Unix-like systems provides two special syntax forms for checking whether a string is empty or not: test -z "$foo" # the length of $foo is zero test -n "$foo" # ...
7
votes
1answer
510 views

80387 transistor count

In 1985, Intel released the 80386, a particularly complex and sophisticated microprocessor for its day, consisting of 275,000 transistors, a rather large number for the day. How many transistors went ...
24
votes
6answers
4k views

Why were pack-in games not usually incorporated on the console mainboard?

In the old days, game consoles were usually sold with a pack-in game, including some iconic titles like 2600 Combat and NES Super Mario Brothers. This makes sense; it provided clear value for the ...
7
votes
1answer
170 views

Automatic booting of SunOS 4.1.14 in qemu-system-sparc: OpenFirmware vs OpenBIOS

In a fit of nostalgia I decided to boot SunOS 4.1.4 up under emulation using qemu-system-sparc. It all seems to work, but I'm trying to remove an annoying manual step. I'm starting qemu-system-sparc ...
4
votes
2answers
252 views

What was the first vector supercomputer?

I am trying to understand the trade-offs between scalar and vector machines, the threshold of complexity/transistor count/performance at which vector machines started to make sense. As data points, ...
7
votes
6answers
3k views

Connecting a Vintage Monochrome Monitor to a Modern PC

I am considering taking my nostalgia for the eighties to the next level and getting hold of a green monochrome monitor. In particular, the nine inch monitor of the Apple IIc, but maybe something else ...
15
votes
7answers
3k views

Could a Z80 address a total of 128 KB of ROM and RAM?

In a nutshell, could the Z80 address 64 KB of ROM and 64 KB of RAM, or just 64 KB for both RAM and ROM? Unfortunately, I couldn't find an exact and a direct answer to my question while searching. ...
18
votes
1answer
3k views

What is the function of this strange IBM apparatus?

Does anyone know what kind of device this is? I found it in my late dad's stuff, probably from the 1970s. It has no number, type, model, serial number or anything else on it that could be used for ...
4
votes
1answer
206 views

Reviving a Powerbook 145B, but it still struggles to power up correctly

Some weeks ago I got a non-working Powerbook 145b for 20€ (~23USD). The first thing I did was to test the power supply, which was giving a good 7.8V. I saw that the battery was still in place and I ...
5
votes
1answer
137 views

Did any S-100 cards have multi-byte peripheral registers?

This question asks about endian issues of the S-100 bus. A peripheral card that has a register larger than one byte (e.g. a 16-bit or larger word) would need to be read/written by more than one ...
9
votes
1answer
1k views

Is there a seamless, Wine-like AmigaOS emulator for Linux, specifically for text-based programs?

After trying out FS-UAE on my Fedora Linux system, which worked quite nicely, I got to thinking. Even though when the Amiga was originally released in the middle 1980s, it was revolutionary in its ...
11
votes
3answers
777 views

How was the main mechanic of the game Qix implemented?

Qix was a quite unique Taito arcade video game that saw ports to nearly any home computing platform of its time. At first glance, the game mechanics seem to be targeted at low-performance hardware - ...
31
votes
5answers
3k views

Did IBM originally plan to use the 68000 in the PC?

One of the big turning points in the history of the industry was IBM choosing the Intel 8088 over the Motorola 68000. Given that most people outside IBM considered the 68000 preferable, there has been ...
2
votes
1answer
115 views

Intel vs Motorola device communication protocols

On this page about "An S-100 68000 CPU Board" it is said: From a hardware perspective there are some very significant differences how Intel and Motorola CPU's talk to the world. Somewhat ...
5
votes
3answers
237 views

Did 68000 on S-100 have any problem with being big endian?

The S-100 bus was extremely versatile; originally designed for the 8080, computers using it had no trouble with the Z80 as a drop-in upgrade, and it even went to 16-bit with the 8086. To my surprise, ...
12
votes
1answer
320 views

Ratio of code density between 8080 and Z80

The Z80 was (except for a handful of tiny incompatibilities) a superset of the 8080, adding a number of new instructions as well as the alternate register set. It seems therefore that it must have at ...

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