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Does “Heart of the Alien” use the same game engine as “Another World”?

Another World is a classical game originally for Amiga and Atari ST and subsequently reimplemented for many retro and modern platforms. As described by Fabien Sanglard the game is implemented in ...
0
votes
0answers
5 views

Is there a list of space-saving techniques for representing constants?

Since numbers in ZX BASIC are always floating point and take up 5 bytes, it's often possible to save space when representing integers by using several tokens, which take up 1 byte each. I know of COS ...
0
votes
1answer
30 views

ResEdit Decompilers

What de-compilers were available for ResEdit? A friend used a de-compiler to break the copy protection on F/A-18 Hornet and I remember having one to examine how programs worked.
3
votes
0answers
30 views

How similar were the X68000 and Capcom CP system?

The Sharp X68000 was used in the development of many Capcom games in the CP system era. It was a formidable workstation but I've also heard it said that the two systems were similar in capability, to ...
2
votes
1answer
103 views

What is the (standardized) weight of a 3.5 inch floppy disk?

What is the weight of a 3.5 inch floppy disk and was the weight ever standardized?
5
votes
3answers
139 views

Has there been any effort to research the undocumented Thumb instructions of ARM7TDMI?

Many CPUs have "holes" in the ISA, where the bit pattern is left undefined. Considering the Z80 and the 6502, many people have mapped out what these undocumented instructions actually do. ...
3
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0answers
62 views

Where can I find a copy of the HiSoft C compiler manual for ZX Spectrum?

I've been able to find the manual for the CPC version of HiSoft C, but not for the ZX. The only ones I could find appeared to have been OCRed, so virtually all of the necessary information was lost. ...
6
votes
1answer
163 views

Who called it “microchip” first?

We all know how Kilby at TI and Noyce at Fairchild invented the integrated circuit. But who called it microchip? Chip?
3
votes
3answers
888 views

9-pin vs 10-pin serial port ribbon cables

I'm (still) putting an old Pentium PC together. I just found that the connectors of my serial port's ribbon cable have one less hole than needed. The socket on the mainboard has 10 pins, but the 10th ...
32
votes
3answers
5k views

Why was `!` chosen for negation?

It seems that the use of the exclamation mark ! to denote negation started with the C programming language (as far as I can tell from my google research). Nowhere though is mentioned who and why chose ...
0
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0answers
128 views

What was the CGI of the 1st Harry Potter movie made on? [closed]

What was the computer system used to created CGI in the first Harry Potter movie? How powerful this computer may have been? Since it was late 1999 I don't suspect Silicon Graphics was still the thing? ...
7
votes
1answer
431 views

How was the wiring color order of the modular connector determined?

In the T568 wiring, sometimes called the RJ-45, pin 3 and pin 6 have the same color pair. I've wondered why it was so decided. I think it would have been simpler to make the 3, 4 and 5, 6 pins the ...
6
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2answers
574 views

Did any ZX Spectrum clones use the Z80's interrupt mode zero?

The standard Sinclair ZX Spectrum only used mode 1 and mode 2 interrupts but the Z80 also has a mode 0 interrupt that the original Speccy never used. But there were many exotic clones of the ZX ...
1
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0answers
52 views

Soltek SL-52B2 motherboard manual

I'm looking for the manual of this motherboard. Google can't seem to find one for this exact model, only similar ones. Help appreciated, thanks!
2
votes
1answer
93 views

Asus SP97V motherboard not powering up

I found an Asus SP97V Pentium-I motherboard. It works with both AT and ATX power supplies. At least it's supposed to, because it actually doesn't. I put a Pentium 120 CPU, four RAM modules and a ...
7
votes
1answer
150 views

How was end-of-file stored on a Commodore 1541 disk? [duplicate]

On a VIC-20 or C-64, you could open a sequential file on a 1541, write exactly N bytes (say, 47 bytes) to it, then close it. Then you could open the same file for reading and start reading byte by ...
3
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0answers
167 views

Why were the audio peak meters removed in Windows 98 but re-added in Windows Vista? [closed]

In Windows 95 and Nt 4.0 and earlier, there were audio meters that represented the loudness of the playing audio (for wave and synth), but it was removed in Windows 98 and NT 5.0. Then, it was re-...
8
votes
1answer
608 views

What's the easiest way to change from MS-DOS 6.22 to DR-DOS?

I am trying to find a way to do task-switching/swapping (not necessarily multi-tasking) in a DOS environment. I have tried DesqView under DOS 6.22 but I don't have any real success. I hear that DR-DOS ...
4
votes
0answers
137 views

What are the differences between MS-DOS and DR DOS FASTOPEN?

OS/2 Museum's history of DOS mentions the FASTOPEN.EXE TSR was introduced in DOS 3.3. Its entry on DOS 4.0 adds some implementation details. It reminded me of the DR DOS FASTOPEN=nnnnn directive in ...
2
votes
0answers
98 views

PC AT power supply not providing correct voltage

I'm refurbishing a Pentium 120 PC with an AT power supply. It seems to work, at least nothing pops or smokes, but there's a slight problem with voltages, particularly on the motherboard connectors. ...
9
votes
2answers
436 views

What was the first programming system to place no limitations on the length of identifiers?

Historically, interpreters and compilers have limited the length of identifiers. For example, FORTRAN I and II considered only six characters to be significant, and LISP 1.5 forbid symbol names to ...
4
votes
2answers
288 views

Can I power a Windows 95-era AT PC with an ATX PSU, like this?

Is this the correct way to make the adapter? Will the "15A 120V AC ONLY" switch damage anything? The switch is illuminated. (glows when off)
5
votes
1answer
305 views

How does an 8086 CPU remember the memory address where it should write back the operation’s result? [closed]

I have an instruction: ADD [BX][SI] + 5FFDH, EABFH and I want to know how it operates exactly on 8086 microprocessors. I've realized that this instruction ADD [BX][SI] + 5FFDH, EABFH, works in this ...
7
votes
1answer
270 views

Did the PAL version of Super Mario Bros. on the NES really have faster music, and if so, why?

I have a real PAL NES hooked up to a modern TV with an AV-to-HDMI adapter (yeah, I'm working on finding a CRT). I bought an EverDrive cartridge for it because I'm a poor person who cannot afford to ...
27
votes
4answers
7k views

Why did old IBM-PC-compatible computers only have 16 colors available?

In the MS-DOS Editor, the only choices for colors were a collection of 16 colors: That's 16 colors: Black Blue Green Cyan Red Magenta Brown White Gray Bright Blue Bright Green Bright Cyan Bright Red ...
9
votes
1answer
181 views

Can you switch the ZX81 ROM to RAM w/o write protecting it and still use ZX81 BASIC?

I built an external 8K RAM circuit that replaced the 8K ROM of Sinclair ZX81 and I also pulled out address lines from the ULA (dogsbody) so that character generation worked. I wrote a small machine ...
14
votes
4answers
2k views

Undocumented instructions in x86 CPU prior to 80386?

I have questions regarding some x86 instructions that were documented for the 80386 and later x86 CPUs, but not for earlier chips. "OR reg/mem16, immed8" (0x83/1) "AND reg/mem16, ...
11
votes
1answer
396 views

What was special about “Vulcan” - the CP/M database program?

The Vulcan DBMS for CP/M micros was originally developed in 8080 assembly language by a contractor working for Jet Propulsion Lab, based on an earlier JPL mainframe program. This code went on to be ...
8
votes
2answers
785 views

What does it mean to byte swap or split a ROM image?

I'd like to understand: What does it mean to "byte swap" when burning kickstart or extended ROMs? Is it the same as "splitting" the ROM? How is it done and why?
1
vote
0answers
117 views

How to save and load CSpect emulator state when emulating ZX Spectrum Next [closed]

I use CSpect emulator for playing a game for ZX Spectrum Next. I wonder whether is possible to save the emulator state to memory and load it in the future in order to have game save/load functionality ...
4
votes
2answers
261 views

Atari800XL Composite video black and white problem

I just brought back to live my old Atari 800XL (it's has 30years with our family), any way, the video composite output is on black and white, I had another 800xl and works fine with that cable, so it'...
2
votes
1answer
176 views

Where can I find the software for “DESIGN: a program to create data entry programs” by J. Michael Wuerth?

I have a copy of the book, DESIGN: a program to create data entry programs by J. Michael Wuerth. Does anyone know where I can obtain a copy of the accompanying software for the book?
7
votes
1answer
1k views

Was there a bug in Wirth's original Pascal compiler?

It appears that both legacy Pascal compilers I have access to (for the BESM-6) contain a bug: they would happily produce code for program test(output);(* may have to omit (output) depending on the ...
13
votes
0answers
319 views

When and where was the ‘dotted sequence of integers’ version numbering scheme invented?

Probably the most widespread software version numbering scheme in use today takes the form of a dotted sequence of integers. Variants of this scheme usually share the following characteristics: ...
1
vote
0answers
212 views

What was this early 2000s software subscription that had a billboard theme and was about music and bands? [closed]

I cannot remember the name of this music software CDs I used to have. We would get it in the mail every month and it had interviews and song samples in a game style UI with a city/billboard theme. ...
57
votes
1answer
10k views

Why didn't Windows 98 need the “Starting Windows 98…” screen?

In Windows 95, when you start up your computer, you see this message: Starting Windows 95... But in Windows 98, this is replaced entirely by the boot logo. Was this just for a better appearance, or ...
2
votes
1answer
217 views

8 pin Mini-DIN to USB converter; where can I buy one?

I have a vintage Sun Microsystems Type 6 keyboard that uses an 8 pin Mini-DIN and I want to use it on a modern computer with at least a USB 2.0 port. I've searched online e-commerce websites but most ...
19
votes
1answer
2k views

Why does the ZX81 not have user definable characters without extra hardware i.e. why could the character ROM not be in RAM?

I know you can use different parts of the 8 KB ROM in Sinclair ZX81 as character ROM by changing the I register, but it seems one cannot change the I register to point to RAM [and have character mode]....
14
votes
2answers
703 views

How much of the Program Segment Prefix area can be reused by programs with impunity?

I am writing a tiny TSR program, and I want it to take as little memory while installed as possible. The memory footprint of every loaded DOS process, including a TSR, includes a data structure known ...
7
votes
2answers
1k views

What technical reasons prevented the Win9x Virtual Machine Monitor from running multiple threads simultaneously?

Were there any inherent limitations in the way the VMM for Win9x was designed that prevented it from being able to run threads simultaneously if the underlying hardware had multiple cores/processors? ...
7
votes
1answer
397 views

Did the original Japanese Tamagotchi device really die *completely* (forever) if the digital pet died? [closed]

Ever since 1997, I've had this "factoid" in my head that the original release of Tamagotchi in Japan had no "reset" feature, and you could not remove the batteries to reset it ...
7
votes
1answer
562 views

What was the first compiler/interpreter/assembler to indicate problematic columns in diagnostic messages?

These days, most compilers and interpreters seem to provide the following in diagnostics: A description of the problem The name of the source file A line number A relevant position within the line ...
14
votes
3answers
2k views

Why did SMARTDRV have to be started with /x when DOS started?

In the default autoexec.bat for DOS 6.22, you see these lines: C:\DOS\SMARTDRV.EXE /X @ECHO OFF PROMPT $P$G PATH C:\DOS SET TEMP = C:\DOS According to this source, /X disables write-behind caching. ...
9
votes
1answer
207 views

How to find what is using Chip RAM?

My AmigaOS should have more Chip RAM available to use than it reports (only 800 kB). Is there a way to find what is sitting in Chip RAM and how to move it to Fast RAM instead?
16
votes
3answers
2k views

What does this line: `T=C/2=INT(C/2)` do? Why is it valid syntax?

I do not understand line 80 of the short Applesoft BASIC program below. Didn't even know it was possible to have a single instruction be T=C/2=INT(C/2). Naturally, I tried breaking this line up / ...
6
votes
0answers
175 views

Was there another dialect of Pascal with this range checking feature?

I've decompiled yet another Pascal compiler for the BESM-6. While it does not implement the full language (for example, packed records and arrays are not implemented, helper routines SEL and INS are ...
21
votes
1answer
2k views

What is the “NES version” of the NES?

This text is displayed on many NES cartridges: This Game Pak cannot be used with the Mattel or NES versions of the Nintendo Entertainment System What is "the NES version" of the NES? Is it ...
18
votes
1answer
2k views

What's the deal with Commodore's RESTORE key?

Most early microcomputers provided either a dedicated key (e.g. Apple ][), keyboard combination (e.g. PC clones), or dedicated hardware button (countless examples) to "Reset" the computer. ...
19
votes
1answer
2k views

What are the screws for on the UltraSPARC?

I fail to grasp what can be screwed on them, can you explain what are these for?
13
votes
1answer
1k views

Is the only reason that my PAL NES is able to run NTSC/American games that it's doing it on an EverDrive?

I have an original PAL NES console. To the best of my knowledge, it is entirely unmodified. I have an EverDrive N8 Pro inside on which I've put a bunch of European/PAL ROMs, but also a few NTSC/...

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