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".
1
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0answers
50 views
Why did SAM on the Apple II use its own DAC?
From the comments on this question, the SAM on the Apple II seemed to use some proprietary hardware to produce the waveform. (I am not counting the option to produce a horrendous 1-bit PWM using the ...
37
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 ...
14
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 ...
3
votes
1answer
150 views
Why did PAL Apple //e motherboards have the AUX slot inline with Slot 3 instead of near the power supply?
The Apple II architecture supported 7 memory-mapped expansion cards which could be optionally installed towards the rear of the motherboard in individual expansion card connectors. On the Apple //e, ...
6
votes
1answer
315 views
Trying to identify an Apple II space trading game
I'm trying to identify a game I remember from my first exposure to computers (the Apple II at secondary school back in the late '70s).
I remember two games I really enjoyed, the first a Star-Trek-...
13
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 ...
10
votes
1answer
637 views
Help identify old Apple game from 80s (Apple II, Apple IIGS)
I am trying to remember the name of a game I played on Apple II or Apple IIGS.
From what I can remember, the beginning of the game you are looking for your lost uncle or something. You to another ...
5
votes
1answer
257 views
Recent article about using Apple II for security purposes
I'm looking for the article for a project. It is fairly recent, may have been a news article, or a blog. It in turn might have referenced a scholarly paper.
Anyway, the gist of the article was that ...
5
votes
2answers
328 views
Is there any benefit of using an Apple Language Card in an Apple IIe?
From what I understand, the original Apple Language Card was basically a RAM expansion card for the Apple II and Apple II+. This expansion increased the on-board RAM by 16K. Normally, if you needed ...
3
votes
2answers
256 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 ...
31
votes
7answers
8k 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
448 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
284 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
128 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
185 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
521 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
218 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
395 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 ...
1
vote
2answers
249 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
168 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
...
32
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
475 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 ...
9
votes
2answers
403 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
223 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
129 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 ...
8
votes
2answers
441 views
How did the Address Decode for Apple II Expansion Cards Work?
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 ...
8
votes
1answer
459 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
176 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
510 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
348 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
511 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
212 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
270 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
273 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
311 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
535 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
640 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
223 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 ...
12
votes
1answer
788 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 ...
18
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
145 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 ...
10
votes
2answers
150 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
160 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
548 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 ...
26
votes
5answers
2k 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
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 ...
