Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange
Join us in building a kind, collaborative learning community via our updated Code of Conduct.

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".

1
vote
1answer
46 views

Labor input for manufacture of early personal computers

In the early days of personal computers, manufacturing was not as automated as it later became, and a factory would often consist of people sitting at tables placing components by hand. I'm ...
26
votes
5answers
7k 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 ...
8
votes
3answers
245 views

How specific was the Apple II floppy disk controller?

One of Wozniak's greatest inventions was the Apple II floppy disk controller, which allowed Apple to avoid going the Atari/Commodore route of making each disk drive a computer in its own right; ...
10
votes
4answers
2k views

What are the rules for Applesoft BASIC formatting for code?

What are the rules for Applesoft BASIC formatting for code? I've been doing some BASIC coding and noticed that: 10 input "some question?"; name$ Will be reformatted as: 10 INPUT "some question?";...
5
votes
1answer
254 views

1980's ROM used which exp(n) algorithm?

In 1980's ROM (Apple IIe, Commodore 64, VIC-20, ...) which algorithm is used to compute exp(x), and where do the coefficients below come from? (Chebyshev, Remez, Pade, ...) .byte $71,$34,$58,$3E,$...
2
votes
1answer
110 views

Turn off Apple IIe sound

Is there a way to disable sound output on the Apple IIe from Applesoft Basic? Can't seem to find this in any of the documentation or online. Update: Found this From http://www.calormen.com/jsbasic/...
4
votes
0answers
151 views

Cost of Apple II switching power supply

Apple went to the trouble of designing a switching power supply at a time when they were still quite new and not widely used for consumer electronics, perhaps because Steve Jobs liked the aesthetics ...
8
votes
4answers
446 views

Columns of text in early microcomputers

As discussed in some previous questions here, 80-column text was established by IBM as the standard for business computing as early as the sixties, but monitors capable of displaying that resolution ...
3
votes
1answer
177 views

Contiki on Apple IIe without Uthernet card

Can I run Contiki on my Apple IIe without an Uthernet card? For example, I was thinking that I could run my Raspberry Pi to emulate a network card through the serial port as a null modem. Any ...
7
votes
2answers
361 views

How did the Microprofessor II have space for a Chinese font in the ROM?

There's an Apple II clone from Taiwan which apparently forgoes the text mode and just has a graphics mode because it's simpler that way to render Chinese writing. It had a 16K ROM, of which 12K is a ...
0
votes
2answers
199 views

What's the fastest Apple II (sans accelerator card)?

The candidates are: Apple IIgs, with its 2.8 MHz 65816 CPU, running in 65C02 "emulation mode" Apple //c+, with 4.0 MHz 65C02, but overclocked to 8.0 MHz Laser 128EX with 3.6 MHz 65C02 I want to know ...
5
votes
2answers
153 views

How can you reset the behavior of ONERR in AppleSoft BASIC?

In an Applesoft BASIC program you can use the standard MS-BASIC ONERR statement to perform error trapping. For example: 10 ONERR GOTO 100 20 POKE 0, 400 : REM INVALID VALUE WILL CAUSE ERROR 30 END ...
30
votes
4answers
6k 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,...
7
votes
3answers
387 views

Practical uses for Applied Engineering 65C816 replacement for IIe?

Applied Engineering produced many advanced and unusual add-on devices for the Apple II product line. One of these was a 65C816 CPU card for the Apple IIe, which replaced the processor with a daughter ...
8
votes
2answers
345 views

Is all 100% of a 64k Apple II memory usable?

Are there any areas of the 64k RAM which are permanently unusable by anything, whether by the built-in monitor ROM or user programs? Looking at $C000-C0FF, this is the "softswitch" area, and as far ...
6
votes
2answers
208 views

In Applesoft BASIC, does combining statements into a single line speed up execution?

In Applesoft BASIC, does combining statements into a single line speed up execution? For example, would this: 10 PRINT "HELLO WORLD" : FOR I = 1 TO 100 : PRINT I : NEXT I Run faster than this: 10 ...
5
votes
2answers
105 views

How to test an Orange Micro Grappler+ card?

Are there some tests that can be done to verify the operation of an Orange Micro Grappler+ printer interface card (1982) in an Apple //e? I've searched around the web and the paper manuals for ...
2
votes
2answers
215 views

Apple II expansion cards

How did the Apple II decode the addresses for the expansion cards? From The Apple Story: Alan Baum helped a lot. I already had some address decoders on the board that decoded every 16th and ...
4
votes
1answer
268 views

Apple II bus: IRQ and DMA priority

One of the weirdest misfeatures of the Apple II - and perhaps the dumbest thing Woz ever designed - is the vestigial priority system for IRQ and DMA on the Apple II expansion bus. Each slot has four ...
1
vote
1answer
153 views

Apple II Plus Modifier key doesn’t work

I received my Apple II Plus today from eBay. I powered up my computer without adding anything into it (it didn’t came with any card either). It started up in the ROM Applesoft BASIC just fine. However,...
6
votes
2answers
461 views

Is the Apple II “No-Slot Clock” compatible with the Thunderclock?

The Apple II series (up until the IIgs) did not have a built in clock. As such, there were a few add-on devices that could be installed that would keep a battery-backed time that could be queried by ...
6
votes
1answer
300 views

Need help identifying math game where equations let you move from room to room?

Can anyone help me find an old math game where equations let you move from room to room? I played the game on an Apple II back in middle school and I want to use it with my daughter to teach her math. ...
9
votes
1answer
404 views

Why are some soft switches on the Apple II only triggered with a write?

The Apple II uses memory mapped I/O and soft switches to do many things. One thing has confused me though: why are some soft switches only activated when written to? For example, 80COLON ($C00D) and ...
5
votes
1answer
193 views

Apple II: LED near joystick connector?

Some Apple II motherboards have a red LED in the back-right corner near the joystick / cassette in/out connectors. I have never seen it illuminated. What is its purpose?
7
votes
1answer
219 views

How can I tell if an Apple II disk image is bootable?

I have around 500 floppy disk images from an Apple II and IIgs BBS/usergroup that closed down recently. Some of the disks are bootable, but many aren't. Is there an easy way to tell if a disk boots ...
5
votes
1answer
251 views

Need help identifying an Apple IIc game/possibly educational with a top-down view

Played it around the end of the 80's but most probably developed between 1981 and 1986. You had control over a person/avatar (not stick figure like, more plump looking) and could walk from scene to ...
3
votes
2answers
261 views

How could a 16-sector PROM Apple II access a 13-sector disk?

When the Disk ][ first came out for the Apple II, the PROMs on the interface card only knew how to work with a 13-sector format. Around 1980, the Disk ][ was updated with 16-sector PROMs either for ...
3
votes
2answers
398 views

How does the Apple II address more than 128KB of RAM?

For the Apple //e, it was very common to have an extended 80-column card installed which brought the machine up to 128KB of RAM via 2 banks of 64KB each. There are soft switches in the $C0xx space ...
9
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 ...
32
votes
3answers
4k 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 ...
11
votes
1answer
567 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 ...
7
votes
2answers
199 views

How do I troubleshoot an 80 column card on an Apple //e?

I have a IIe (boots as enhanced: Apple //e), motherboard 607-0187-A, and 80 column text card 607-0103-J. They came together and I think they're compatible, but not sure. When I boot to DOS 3.3 then ...
11
votes
1answer
666 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 ...
17
votes
5answers
1k 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 ...
10
votes
1answer
128 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 ...
10
votes
2answers
1k views

Which Apple floppy drive is compatible on both Apple IIc and Macintosh

I have an old Apple IIc (not Plus) and an old Macintosh Plus (1MB RAM). I want to buy an external 3.5 inch floppy drive that works on both machines, that way I don't need two different drives around ...
9
votes
1answer
86 views

Apple II: ProDOS partitions on floppy disks?

On the Apple II using ProDOS, was it possible to create partitions on a floppy disk? Would it be possible to have two or more partitions on a 140k 5.25" or 800k 3.5" disk? (The question here is not ...
9
votes
1answer
144 views

Apple II: What type of partition tables were used?

What type of partition table was used with ProDOS? ProDOS (8-bit) version 1.2 was available in January 1983, one year before the Macintosh was released, so it is unclear to me if ProDOS 1.2 used the "...
8
votes
1answer
423 views

Using Apple II with modern monitor displays snowflake

I recently picked up a (seems like) fully functional Apple IIc on eBay to play around with. I do have a modern TV that has RCA input port that the Apple IIc supports. However, when I plug in the Apple ...
25
votes
5answers
1k 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 ...
20
votes
2answers
1k 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 ...
17
votes
2answers
432 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 ...
6
votes
0answers
216 views

Did the Apple ][ ever ship with the Autostart ROM

Did the Apple ][ ever ship with an autostart ROM from the factory or were they all the older ROM with Trace/Step? My guess would be that once the ][+ started shipping then new Apple ][ production (...
18
votes
3answers
462 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 ...
11
votes
1answer
220 views

Apple II SCSI: Maximum drive / partition size?

Using an "SCA to 50-pin adapter", it is possible to use a 300 gig Ultra-320 SCSI drive from 2004, with an Apple II outfitted with the Apple SCSI controller. It seems possible for the electronics to ...
13
votes
2answers
303 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 ...
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 ...
9
votes
2answers
507 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. ...
11
votes
2answers
577 views

Why was Brøderbund's RWTS18 incompatible with the Laser 128?

The V-Tech Laser 128 is an Apple II clone. This machine uses a clean-room copy of the Apple II BIOS and was intended to be compatible with Apple software. However, Brøderbund's games stored with the ...
7
votes
4answers
231 views

Cost of expansion slots

Among other early computers, the Apple II and IBM PC made the consequential decision to provide internal expansion slots. How much did this add to manufacturing cost? Intuitively, it seems like it ...