Questions tagged [apple-ii]

For questions about the Apple II series of personal computers, and related software and hardware. For questions about Apple hardware in general, use the tag "apple"; for questions about the IIgs in particular, use the tag "apple-iigs".

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46
votes
13answers
17k views

How was it back then in 1984, when the Apple II had color, and the new Macintosh didn't?

I imagine it being a huge downgrade for some, not to have color on the Macintosh. Macintosh games were black and white in the beginning, while Apple II had color. I'm especially interested in ...
39
votes
3answers
4k views

How did Apple ][ basic programs protect against listing?

I seem to recall from my high-school days that certain Apple ][ programs protected themselves from being listed and therefore modified. If you tried to do it, the machine would simply reboot. How ...
36
votes
7answers
9k views

How did Apple fail to tap the business and scientific markets?

Currently reading an excellent book called Blue Magic: The People, Power and Politics Behind the IBM Personal Computer, which is just what it says on the tin; highly recommended to anyone who wants to ...
36
votes
4answers
7k views

What determines the color of every 8th pixel on the Apple II?

On the Apple II there's an interesting way to add a little color to the bitmap, since the high bit select the palette used for the three-and-a-half pixels represented by the byte. Like this: 0: Black,...
35
votes
3answers
5k views

What was the point of Apple Pascal having its own file system?

Apple's UCSD Pascal for the Apple II used its own file system rather than the existing DOS 3.3 of the day. I'm not sure if it overlapped SOS at all, but regardless of timelines it seems that the ...
30
votes
5answers
3k views

Does every retrocomputer and console with NTSC composite output have 'artifact color' ability?

Artifact color is heavily associated with the Apple ][, since that is the only method the machine had to produce a color display. I was looking at the fantastic demo for IBM PC + CGA, 8088MPH, and I ...
30
votes
1answer
1k views

How does “bit-slip” copy protection work?

Some Apple II 5.25" floppies used a special pattern of bytes that could not be automatically detected by disk copying software. How could the pattern be invisible to disk copiers but detectable by ...
29
votes
5answers
8k views

Why did the Apple IIe make a hideous noise if you inserted the disk upside down?

When I began high school in 1987 all the computers in the lab were Apple IIe desktop computers. A question has haunted me since then: if you inserted a floppy disk "upside down" the Apple IIe would ...
29
votes
4answers
1k views

Absolute maximum number of nibbles on an Apple II floppy disk track?

The Apple 2's disk drive controller and 5¼" floppy disks have the following metrics: The disks is spun at (roughly) 300 RPM (Revolutions per Minute), which means it takes = 1000 ms/sec / (300 RPM / ...
27
votes
2answers
3k views

Apple II: Applesoft BASIC memory management

I am trying to write an Applesoft / floating point BASIC program using high resolution graphics and some assembly language code. My BASIC program is quite large, and after running the program for a ...
26
votes
3answers
2k views

What do the '80/40' and 'keyboard' buttons on my Apple IIc do?

Above the keyboard of my Apple IIc there are two buttons that say "80/40" and "Keyboard". On my machine, they both kinda feel broken. When I press them, they recede into the case and remain there for ...
24
votes
4answers
4k 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 ...
24
votes
2answers
3k views

Why did the original Apple //e have two sets of inverse video characters?

According to Apple II Technical notes Mouse #6, updated January 1989, In unenhanced Apple IIe computers, the alternate character set contained two sets of inverse uppercase characters. In the ...
23
votes
4answers
5k views

What is DRAM refresh and why is the weird Apple II video memory layout affected by it?

I've roughly known the concept for years, but never really understood it. Back in the day, two types of RAM typically used in home computers: static and dynamic RAM. Static RAM (SRAM) was apparently ...
23
votes
5answers
4k views

Over its lifetime, how many Apple II computers were sold?

It would be nice to break it down by model if possible.
22
votes
2answers
983 views

How can I programmatically tell which version of Apple II my code is on?

There are minor and major differences between the many Apple II models. I would like to detect whether my 8-bit assembly language program is running on a II, II+, IIe (enhanced or not), or ///, and ...
22
votes
1answer
2k views

Why was it possible to cause an Apple //e to shut down with SHIFT and paddle button 2?

Looking at the MAME driver for the Apple //e, I noticed an interesting comment: NOTE: On real IIe and IIe enhanced h/w, pressing SHIFT and paddle button 2 will short out the power supply and cause ...
22
votes
2answers
917 views

Why did Apple remove booting from external drives in later IIc ROM versions?

Apple II computers don't come with DOS in ROM, but rather need to boot from a floppy disk to make the disk drives usable. The IIc was the first Apple II that came with a built-in disk drive, so ...
21
votes
2answers
756 views

How do I use shadowed memory to render Super Hi-Res quickly?

The Apple IIgs video memory is controlled by the 1MHz Mega II chip, so directly accessing the Super Hi-Res page in bank $E1 is slower than accessing other memory. How can I render in "fast" memory, ...
21
votes
2answers
2k views

What are the “Screen Holes” in Apple II graphics?

I've read the term screen holes many times in the context of Apple II graphics. From what I understand, it has something to do with the interleaving storage of graphics (or was it text) and that some ...
21
votes
3answers
2k views

What makes slot 7 of the Apple ][ unique from 1-6 and how was this used?

In the Apple II, there are three unique slots (depending on model): Slot 0 (on the ][ / ][+) which is typically used for language cards. "Aux" slots in the //e and IIgs, typically used for memory ...
19
votes
4answers
971 views

How were binary subroutines embedded in Integer BASIC programs?

Programs written in Apple's Integer BASIC sometimes had bits of machine code embedded in them. This was more convenient than loading the code separately, especially when the program was loaded from ...
18
votes
5answers
2k views

Can a retro-computer be a useful way to learn computer-architecture fundamentals?

I've been reading about the fundamentals of computer architecture, but I think I could get a better grasp of the basics if I could could have an actual device to play with. I had considered building ...
18
votes
2answers
1k views

Apple // screen editing

I've heard mention many times of screen editing commands on the Apple // for fixing typos in BASIC programs (and patching code in the monitor?). I did not learn these growing up, never having the ...
18
votes
3answers
998 views

Did the Apple IIe Platinum include all feature enhancements from the Apple II line?

Not including the Apple IIgs, did the Apple IIe Platinum include all enhancements made by Apple? For example, the first Apple IIe couldn't utilize the Double Hi-Res mode from what I understand. In ...
18
votes
4answers
4k views

Quick way to tell how much RAM an Apple IIe has

What is a simple way to tell how much RAM an Apple IIe has? The main RAM is fixed, but Aux RAM can vary. I'd like a solution that can be typed quickly from the keyboard: the context is that I'm ...
18
votes
2answers
1k views

Transferring from Apple II

I have also found a working 1978 Apple II. Now my dad wants me to transfer its data to another device without using fancy Apple II exclusive hardware and if possible, through a cassette port. Now, ...
18
votes
2answers
607 views

How many versions of DOS were there for the Apple II and what were the differences?

DOS 3.3 was the most common before ProDOS. How did it differ to DOS 3.2 and what versions were there before that?
16
votes
1answer
2k views

How do accelerators and CPU cards work on the Apple II?

An Amiga 1200 exposes the entire CPU bus on the expansion port, so that an accelerator only needs to assert BR which causes the onboard CPU to stop all computation and electrically disconnect from the ...
16
votes
1answer
797 views

Why is the Apple II hi-res HGR command so slow?

The Apple II hi-res screen sits on 8KB of memory, so it should be possible to erase it quickly. The Applesoft HGR command is slow enough that the "Venetian blind" erasure is clearly visible. ...
16
votes
2answers
736 views

Apple II: DOS 3.3 Virus?

Does anyone know the source of this Apple II DOS 3.3 virus that infected my disks back in the 1990's? I got it from a public domain disk collection that was given to me by a friend, called the ...
16
votes
3answers
989 views

What are the differences between the versions of AppleSoft BASIC?

Apple did make some changes to AppleSoft BASIC over the years between the first version on the Apple II and the last version on the Enhanced IIe and IIe card. What are the differences between the ...
16
votes
1answer
333 views

Did any Mockingboard game use the VIA timers or interrupts?

There were only a small number of games that supported any of the Apple II sound cards such as the Mockingboard. From those games that used the Mockingboard, did any of them utilize the on-board VIA'...
15
votes
4answers
812 views

Can the CSG 65CE02 CPU be used to accelerate an Apple //e or //c?

The CSG 65CE02 is an improved 6502 microprocessor that was shipped in small quantities by Commodore around 1988. It is used in the Amiga A2232 multi-port serial controller card, and that would be the ...
15
votes
1answer
2k views

Why did the Apple IIe use a 2 MHz-rated 6502, even though it ran at only 1 MHz?

The Apple IIe was designed to be timing-compatible with the Apple II+ so that timing-depndent software (such games and copy-protection systems) and hardware designed for the Apple II and II+ would, ...
15
votes
3answers
485 views

What are the normal signals on a 65C02 in an Apple IIe?

I'm troubleshooting a dead Apple IIe enhanced, and I'm having trouble finding documentation on testing the 65C02 (as opposed to the 6502). Specifically, I've found using a logic probe that pin 6 (...
15
votes
2answers
323 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 ...
14
votes
12answers
4k views

Late 1970s and 6502 chip facilities for operating systems

I'm quite unfamiliar with how operating systems used to be written but its clear to me that operating systems were clearly written for these systems. I'm particularly interested in how operating ...
14
votes
4answers
1k views

Was the Apple II ever sold in kit form?

In the June 1977 issue of BYTE magazine I saw an advertisement stating you could order an Apple II and it had a price list. One of the columns was titled "Apple II Board-only". The price for that ...
14
votes
2answers
3k views

1980s game with a guy with an axe on a flying disc

I'm trying to identify a game I remember from the 1980s. The game was shown from a bird's-eye viewpoint (or maybe isometric?), on Apple IIe, IIRC. You controlled a guy with an axe, who was ...
14
votes
1answer
910 views

What was the change to the Apple //e motherboard that allowed for Double HiRes graphics?

Double Hi-Res graphics (DHGR) was a nice addition to the Apple ][ line as it allowed for higher resolution 560x192 graphics with 16 colors in comparison to the traditional 280x192 with 6 colors. It ...
14
votes
1answer
349 views

How does ProDOS allow for multiple volumes to exist on a single device?

On the back of this question, it got me thinking that it has always been that ProDOS would only support a ",D1" and ",D2" on a slot, i.e. slot 6 would have two addressible drives. With my 20MB Sider ...
13
votes
2answers
903 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 ...
13
votes
1answer
568 views

Odd tokenizing in Integer BASIC

While researching the underpinnings of Integer BASIC (IB), I came across an oddity I'm hoping someone can explain. Unlike MS-derived systems, IB converted numeric constants to their 16-bit ...
13
votes
1answer
1k views

Did the PAL version of the Apple II use a different clock frequency?

The Apple II used a 6502 CPU clocked at 1.023 MHz which was tightly tied to the NTSC frequency (1/14 of crystal, 3.5 color clocks per CPU cycle). It is well known that the Disk ][ was primarily ...
13
votes
2answers
674 views

How to connect an Apple IIe to an external Sider hard disk drive

I am a sucker for 8 bit junk components, and recently picked up a Sider hard disk for my Apple //e. I was able to talk myself into the purchase by fondly remembering how I lusted after this piece of ...
13
votes
1answer
990 views

Early Apple assemblers, getting hold of them

The apple ][ history site https://apple2history.org/history/ah17/#05 has a section on assemblers with these interesting snippets: TED/ASM: Developed at Apple and smuggled out the doors around May ...
12
votes
2answers
1k views

Was Apple DOS 3.3 created because of the Apple III?

I recently read a document which discussed how the Apple III would implement the Apple II emulation mode. On page 20, it goes on about difficulties involved with how the Apple III would have ...
12
votes
2answers
969 views

How was Prince of Persia “better/faster” with RWTS18?

I was reading about Prince of Persia over at POP Code Review. In that article, the writer printed an interview with Roland Gustafsson, the inventor of RWTS18 copy protection for the Apple II series. ...
12
votes
2answers
898 views

What are my modern options for loading programs and data files on the Apple IIc?

I've recently acquired an Apple IIc. The internal 5.25" drive does seem to make appropriate noises at boot, but I do not (at least not yet) have any floppy disks, with software or otherwise. It's an ...