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13
votes
2answers
945 views

How could high level functions with return values map to 6502 assembly? (if at all possible)

What sort of code could be used to substitute a high level function with a return value to a 6502 subroutine? Take this C-like function for example. byte func(byte a, byte b, byte c) { d = (a + b)...
8
votes
3answers
423 views

Origin of dealer networks

Roughly speaking, the two main ways to sell computers are, and particularly were in the old days, Three digit price tag sold to individuals => mass market, department stores and suchlike. Four digit ...
19
votes
4answers
656 views

When or should we expect our 8-bit motherboards to fail due to the capacitors?

I would assume that most people who have been trying to keep these old micros working are well aware of the finite life of components, which is the idea that age will eventually cause things to fail. ...
11
votes
1answer
1k views

Did all NES “Black Box” games come in carts with five screws?

When the NES was released, there were a list of original titles from Nintendo such as Duck Hunt, Super Mario Bros. and Metroid. These titles came in a distinctive box that was mostly black. Plus, the ...
10
votes
3answers
668 views

How does 6502 machine code process $ (address) VS #$ (value)?

How does the 6502's machine code process $ vs #$, as in it's assembly language? Does every piece of machine code have an extra byte or something telling to use addresses or values or was it something ...
5
votes
1answer
365 views

Other than Ocean, what other famous loaders were there? [closed]

Many people are familiar with the awesome Ocean loaders from the 8-bit days. For those that are not, "loaders" are small programs that were usually artwork and music (sometimes games) that were ...
18
votes
2answers
1k views

How are Amiga libraries structured?

In this Crash course to Amiga assembly programming, the author loads A6 with a constant, and then regularly jumps to offsets from that constant. He explains: All functions within that library can be ...
9
votes
2answers
2k views

Alternative to Amiga 520A Video Adapter

So I snagged a North American Amiga 500 on sale at a flea market. I purchased a DSub to VGA connector in the hopes I could get some color output. After getting strange Horizontal sync on my monitor, I ...
10
votes
1answer
258 views

Does a CDC 1604 emulator exist with a functional FORTRAN compiler?

The first FORTRAN compiler for the Soviet BESM-6 mainframe was written by means of manually retargeting the assembly code of the CDC 1604 FORTRAN compiler donated by CERN to JINR. As a result is it ...
55
votes
6answers
7k views

Reason for the Amiga clock speed

The Amiga used a CPU rated for 8 megahertz, but clocked at 7.14 megahertz. What was the reason for this number? I remember it was something to do with a multiple of the frequency of the video ...
9
votes
2answers
332 views

S-100 bus and device drivers

It is said that the S-100 bus provided a standard hardware format for expansion cards across many models of computers, including ones using different system software and even different CPUs. Having ...
9
votes
1answer
355 views

NTSC scan lines and vertical resolution

From https://en.wikipedia.org/wiki/BBC_Micro "the height of the graphics display was reduced to 200 scan lines to suit NTSC TVs". But NTSC is supposed to have 241 visible scan lines per half frame. ...
3
votes
1answer
367 views

Installing hdd on PhoenixBIOS A486 on Gateway 2000 4DX-33

I'm fixing up a Gateway 2000 4DX-33 which came with a Fujitsu hard drive. The CMOS battery was dead after over 20 years without use, and needed to be replaced. This meant that all BIOS settings were ...
51
votes
12answers
11k views

What early home computers have more than one CPU, where both could be used by the programmer? [closed]

I am interested to know if any computers that are on-topic for this site had more than one CPU, where this plurality could be leveraged by a programmer. Some cases I don't so much care about: The ...
4
votes
0answers
119 views

Can a modern 1.44MB floppy drive work with an Amiga 2000? [duplicate]

Can an Amiga 2000 (or even A500) be made to easily work with modern 1.44 MB drives? Meaning, is it just a matter of pin mappings or are the drives just too incompatible? I realize there are other ...
14
votes
4answers
698 views

Appropriate battery replacement for my A3000

I know the interwebs are full of information relating to the replacement of batteries for various computers, and the Amiga's are no different. But before I do anything rash, I wanted to ask for some ...
15
votes
1answer
357 views

Seeking details relating to Amiga 3000 serial numbers

I am the original owner of my Amiga 3000. As I remember it, I purchased the machine fairly early after release. I'm cleaning and detailing the machine, and I took a quick picture of the serial ...
10
votes
1answer
691 views

What kind of EPROM was used for the Apple //e character generator, and how do I write a new one?

I have an old Apple //e clone, bought in Brazil (but assembled who-knows-where-on-Earth) that has not been touched for over 15 years. At least, from what I could see, it is a //e -- but not enhanced, ...
12
votes
1answer
319 views

Typical academic PDP-11 configuration for emulation

What was the typical configuration — CPU, memory, disks (number and type), printers, terminals, OS, etc — for a university PDP-11 system in the mid-late 1970s? I'm more interested in the FORTRAN/BASIC ...
19
votes
1answer
3k views

Game cartridge save-game battery lifetime

Some cartridges on older consoles (like on the SNES) had battery save in them, so you can turn off the console, come back some time later and continue where you left off. These use an actual battery ...
12
votes
1answer
1k views

Historical cost of computing (when was $1/FLOPS crossed?)

The relevant Wikipedia page has a large gap between 1961 and 1984, not allowing to estimate, even approximately, in what year the symbolic threshold of $1/FLOPS (or, as the wiki table puts it, $1bn/...
13
votes
2answers
765 views

Historical price of ROM

Historical price charts for RAM are quite readily available, e.g. in the mid-seventies a ballpark figure was a penny a byte. What was the price of ROM (assuming you were getting the chips produced in ...
37
votes
4answers
20k views

Commodore 64 to modern TV

I've been thinking about getting a Commodore 64 machine. However, I realise there's obviously no video cables I have that will work. But when I looked online there are many people using S-Video to VGA ...
7
votes
4answers
818 views

Magnetic tapes as a random access medium?

A two-part question: How widespread in legacy systems was the practice of using magnetic tapes as a genuinely random access medium at the OS level by pre-formatting them in a way before the first use,...
11
votes
1answer
839 views

What cleaning/repair can be done to a Mega Drive cartridge slot?

My Mega Drive's cartridges rarely boot. It's to the point where I sometimes don't want to change the current game because it'll mean 15 minutes of me constantly taking out and re-seating the next ...
6
votes
1answer
87 views

HD63B03R timer interrupt frequency

I am trying to maintain an old procuct for my employer, based on an HD63B03R which is a 6800-style micro. The crystal on the PCB generates a 4.75MHz clock. I believe from the data sheets found on t'...
12
votes
3answers
564 views

Which programming systems used object files on punch cards?

In a batch programming system developed in the late 1960s - early 1970s at the Joint Institute for Nuclear Research in the city of Dubna near Moscow, it was possible to dump object files to punch ...
1
vote
1answer
352 views

How to I give instructions to a Z80 CPU [duplicate]

I found a Z80 CPU lying around my house. I've search all over the Internet but I still don't know how do I input stuff and tell it what to do. Help me please
18
votes
2answers
3k views

Wiring a Zilog Z80

I've recently got hold of an old Zilog Z80 microprocessor and I know how to clock and test it. I do not however know how to connect RAM, I/O ports, control switches (for programming instructions into ...
8
votes
3answers
984 views

Replacing Amiga 9 pin D-Sub mouse cable

I have an original Amiga "tank" mouse, the PCBs are good, but the cable is clearly faulty as the Y axis and left mouse click doesn't work when it is tilted to the right. I need to replace the cable ...
1
vote
2answers
259 views

How to render FORTRAN overprinting in HTML? [closed]

Consider a FORTRAN program РRINТ 1 1 FОRМАТ(1Х,’ GООD ВУЕ НЕLLО, WОRLD’/’+ХХХХ ХХХ’) ЕND (YMMV re the number of leading spaces to align Xes with "GOOD BYE") Its output, using the SIMH ...
15
votes
2answers
282 views

Connecting an Apple //e with a Super Serial Card to an Android device via a USB to DB25 cable

I have an Apple //e, and I quite enjoy using it as a dumb terminal to my Raspberry Pi from time to time. Recently, I came across a few cords that could connect my Android phone (a Pixel) to the DB25 ...
22
votes
4answers
3k views

How did the Apple II forward binary instructions to the Z80 software card with CPM?

Microsoft produced the Z80 Softcard for the Apple II enabling it to run CPM and many Z80 binary programs. This seems to be an unthinkable achievement. (For a kid who had an Apple IIe but was only a ...
12
votes
2answers
538 views

BBC Master 65C102 co-processor — test memory

Out of the blue the other day, my friend found an internal 65C102 co-processor for the BBC Master in his attic, and gave it to me. It wasn't in particularly good physical condition (all the pins were ...
11
votes
1answer
462 views

What is known about the Wang VS series CPUs?

I'm trying to do research about the Wang VS series, and there's very little on these computers on the internet (as the company was effectively dead before the internet era, this is hardly shocking). ...
5
votes
1answer
349 views

When were floating point rounding modes first implemented?

It appears that at least some pre-IEEE 754 computers had only one hardwired floating point rounding mode, e.g. away from zero as in PDP-11 (page 154 of PDF). Which historical architectures were the ...
8
votes
4answers
1k views

Were people building FPGAs out of TTL logic prior to the first sales in 1984?

My experience growing up was that my Dad would program 'EEPROMs' or Flash ROMs from his Apple IIGS. (I don't know if that is similar to an FPGA or not). He used these in custom wire-wrap computers he ...
12
votes
1answer
145 views

Videoprocessor with custom horizontal sampling

I have a variety of videoprocessors (Micomsoft Framemeister, Micomsoft SC-512N1-L/DVI, Sync Strike) to help me get the best possible RGB picture out of my retro computers/consoles. However one issue ...
11
votes
4answers
680 views

How to build a workstation to handle bulk quantities of floppy disks?

I need to handle bulk quantities of floppy disks, where I archive their contents, then recycle them by formatting them for use on old Amiga/Atari/MS-DOS computers. I have a 3.5" floppy disk drive ...
13
votes
2answers
779 views

Heating issues in Apple II?

My Apple II has been getting really hot in use, I've cleaned it, so I don't think dust is an issue. Is there something wrong with the hardware that could be affecting it? I've had Apple IIs overheat ...
14
votes
10answers
3k views

Were people building CPUs out of TTL logic prior to the 4004, 8080 and the 6800?

I've just finished reading Charles Petzold's book, Code: The Hidden Language of Computer Hardware and Software. In it Charles explains building relays into gates, gates into logic components, and ...
9
votes
1answer
221 views

Remote Debugging on the Atari ST

Were there ever any remote debugging tools for the Atari ST line of machines? When developing games in full screen modes, switching away to a debugger seems quite cumbersome if you need to remember ...
7
votes
1answer
169 views

Was there an Apple IIc clone other than the one from V-Tech?

When I was a kid, my aunt had an "official" Laser 128 that was made, IIRC, by V-Tech. Later in life, I bought a "Laser 128" off eBay but I don't know if it was really from V-Tech or not. Even though ...
22
votes
1answer
773 views

How does the NES PlayChoice arcade's security EPROM work?

I've read that the PlayChoice 10's security system includes a 64-bit serial EPROM that gets compared against the first 64 bits of code, and that it's possible to swap the ROMs between compatible ...
31
votes
1answer
2k views

Where and what was Haunt.bat? A game pre-loaded on a c1992 PC

This doesn't belong on the gaming SE, so I'm trying my luck here. I'm looking for any info I can get on an old game that I simply known as "Haunt.bat". Here is the back-story: In the mid 90's a ...
23
votes
16answers
2k views

What computers had redefinable character sets?

My first computer was an Exidy Sorcerer, bought in the late '70s. It featured a full keyboard including lower case, on screen text of 64 B&W characters by 30 rows, 2 MHz z-80 processor, up to 48 ...
9
votes
6answers
1k views

Is there a C64(or any other) emulation that can be run in terminal?

I was looking for a C64 type computer that can be used in the terminal. Can I code one or is there one on the interwebs?
7
votes
1answer
248 views

6 Player X-Men Arcade Cabinet Compatibility

I've got a 6-player X-Men Arcade cabinet and I was wondering what other boards might be compatible with it. Can I use any Jamma compatible board? Will the dual monitors just mirror? Here's a link to ...
9
votes
2answers
386 views

Which LCD technology was used in Game and Watch?

TL;DR - Was the LCD technology in Game & Watch passive (or active)? If so, was the technology used Twisted Nematics (and at which point, if at all, were Super Twisted Nematics employed, and in ...
10
votes
1answer
385 views

On-disk structures for Files-11 format (RSX11)

I'm looking for an explanation, or a link to documentation of the on-disk structures of the Files-11 format, that is, the format of disks used by RSX-11 on the PDP-11. Also known as ODS-1, the ...

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