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16 votes
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What's the name of this Apple monitor

NEC Character Display, Model JB-1201M(A). It’s a 12” monochrome green display, manufactured in Japan circa 1981. Approximate dimensions are 14” x 12” x 11 1/2”. Further details found at: https://www....
Jim Withrow's user avatar
14 votes
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What's the correct Unicode code point for the Apple IIe's "delete" symbol?

TL;DR: There is no 'REVERSE FIVE-BY-FIVE CENTERED CHECKER BOARD' (*1) in all of Unicode's blocks. Closest by looks and positioning might be the "REVERSE FOUR-BY-FOUR CHECKER BOARD" U+1FBA6 ...
Raffzahn's user avatar
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13 votes
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Help understanding TAIPAN source code for the Apple II

You don't need to follow the listing far to see the problem. Line 10 ends with GOTO 10000, and 10000 starts with CALL 6147, which is $1803, smack in the middle of the Applesoft source code, which ...
Nick Westgate's user avatar
12 votes
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NTSC scan lines used by 8-bit computers

I found one document which might shed some light why 192 lines was used before 200 caught on. The TI 99/4 used a TI TMS9918 VDP, which based on the document, was designed as a chip for simple low cost ...
Justme's user avatar
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10 votes

NTSC scan lines used by 8-bit computers

Older television sets used round picture tubes with a bezel to mask off the edges of the scanned area. Picture tubes were often circular, and to maximize useful areas, the image was expanded to the ...
supercat's user avatar
  • 37.1k
10 votes

NTSC scan lines used by 8-bit computers

Similar to the TI VDP answer, have a look at the Apple text mode layout described in this answer. (And keep in mind that the graphics video layout is based on the text layout). There are 40 characters ...
dirkt's user avatar
  • 28.2k
10 votes

NTSC scan lines used by 8-bit computers

Conjecture #1: NTSC title-safe area (unlikely) An NTSC video frame has 525 lines. After subtracting the 21 lines of vertical blanking, and the 20% of the visible area that was considered non-title-...
dan04's user avatar
  • 1,084
9 votes

What's the correct Unicode code point for the Apple IIe's "delete" symbol?

Only because @trikly asked (in this comment), from the relevant Unicode documentation(PDF), the three new "Specific symbols for delete" that have been accepted for future inclusion in the ...
FeRD's user avatar
  • 381
8 votes

How can I connect a PIA or VIA chip to the Apple IIc?

Ian Kim's Mockingboard 4C shows how it is done. This card includes a 6522 VIA chip (actually a 65C22 since those are still in production) as part of the daughterboard. It connects via the CPU socket. ...
Ian Brumby's user avatar
8 votes
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How to change what program Apple ProDOS 'starts' when booting

Sorting the root directory to put the desired .SYSTEM program first will fix the issue. You can sort a directory on a ProDOS disk with the ProSel-8 disk utilities or Copy II+. You can also just ...
fadden's user avatar
  • 9,060
7 votes

What were the differences of the various AE RamWorks cards?

What were the differences of the various AE RamWorks cards? (Base Board) Memory size. There were 3 versions produced by AE back in the day, the RamWorks, RamWorks II, and RamWorks III. The original ...
Raffzahn's user avatar
  • 225k
7 votes

Help understanding TAIPAN source code for the Apple II

You might have more luck with the BASIC program from this disk: Taipan Hayden Book Version, which was apparently keyed from the Taipan: A Historical Adventure For The Apple Computer book. It at least ...
scruss's user avatar
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6 votes
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How Can Apple II DOS 3.3 Floppy Disks be Restored after Formatting with INIT?

The INIT command directs the drive to move the head to each of the first 35 tracks in turn, and overwrite the entire contents thereof. In performing this process, the drive uses two coils: an erase ...
supercat's user avatar
  • 37.1k
5 votes

Extensions to Apple BASIC with ampersands

A little late to the party but I remember doing this back in the early 80's, it was definitely the & "extension" used in Applesoft. Like Patrick mentioned I also remember combining ...
JohnL's user avatar
  • 51
5 votes

What were MECC's specifications for a school computer in 1978?

Requirements are made to fit Since we are already somewhat off topic, it may help to add a generic view about a standard procurement process in every bureaucracy, no matter if state, school or company:...
Raffzahn's user avatar
  • 225k
4 votes
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Getting garbled text when using ADTPro with Apple IIc and serial connection

It turns out the issue lied in the IIc null modem cable. After receiving a replacement, the connection worked perfectly and I was able to immediately load ADTPro via the bootstrapping process.
Idrees's user avatar
  • 91
4 votes

What were MECC's specifications for a school computer in 1978?

That question is, unfortunately, borderline off-topic, because, in the end, it's not at all about computers, but politics. It seems to start on a number of false premises: The educational segment is ...
tofro's user avatar
  • 35.2k
4 votes

How can I connect a PIA or VIA chip to the Apple IIc?

Physically, the simplest and most non-invasive method to connect would be the CPU socket. Most of the contemporary IIc expansions used that. From a "virtual slot" perspective, all of the ...
tofro's user avatar
  • 35.2k
4 votes
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ProDOS BASIC.SYSTEM overwrites RNDL ($4E) - how to get random numbers

It seems that RANDL ($4E) and RANDH ($4F) were re-purposed as a pointer named usrbuf that's used extensively throughout ProDOS. It's used as the destination for writing the bytes read from a file. ...
Nick Westgate's user avatar
4 votes

What's the correct Unicode code point for the Apple IIe's "delete" symbol?

In order to determine what Unicode symbol should be associated with that character, one would have to ascertain what the dot pattern was supposed to represent. The particular pattern of dots used for ...
supercat's user avatar
  • 37.1k
4 votes

Apple ][ nibble disk format specification

I've been generating documentation on various Apple II (and Macintosh) formats as part of the development of CiderPress II. The general layout of nibble data is described in this document, and the ...
fadden's user avatar
  • 9,060
4 votes
Accepted

Apple ][ nibble disk format specification

There is no spec as such, except for the behaviour defined by what Saltine's Super Transcopy program does. (It's a great hack using the track read code from Essential Data Duplicator as mentioned here....
Nick Westgate's user avatar
4 votes

How to change what program Apple ProDOS 'starts' when booting

I would be astounded if the answer is to "delete everything and add files in the correct order" Jup, that's 'a' solution :)) ProDOS only expects a single SYSTEM to exist on the boot volume. ...
Raffzahn's user avatar
  • 225k
3 votes

What were the alternative graphic cards for the Apple II?

One very high-resolution graphics card that could be used with Apple ][ and //e systems was the IO Research Pluto This went up to 1024x768, in up to 24-bit colour. It did not go inside the Apple case: ...
John Dallman's user avatar
  • 13.4k
2 votes

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

What most answers here missed is that it was not the colour or resolution that the Lisa first, the Macintosh both inspired by the Xerox Alto, then brought to the table that was considered progress. It ...
Patrick Schlüter's user avatar
2 votes

What is likely cause for sudden auto-rebooting of Apple II+ with Disk II?

Again, I pulled and reseated both adapter cards, from slot 0 (Language card) and slot 6 (Disk Controller); I pulled and reinserted all cables from all cards & connectors on mother board. I pulled ...
JTyler2's user avatar
  • 93
1 vote
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US equivalent of the Microvitec Cub monitor

I don't know whether this was regional but all the Apple computers at schools in my area (northern Illinois) as a kid in the mid-80s had Amdek monitors, usually a 300A.
Wildcat Matt's user avatar
1 vote

ProDOS BASIC.SYSTEM overwrites RNDL ($4E) - how to get random numbers

If you want to go straight into algorithms that use random numbers without having any keyboard input (e.g. boot apple, launches ProDOS, and this application is the first .SYSTEM or STARTUP that gets ...
bjb's user avatar
  • 16.4k
1 vote

ProDOS BASIC.SYSTEM overwrites RNDL ($4E) - how to get random numbers

RNDL/H is incremented by the standard keyboard routine when waiting for a key as described in the Technical Reference (P.62 of the Apple II Reference Manual) And shown in the corresponding monitor ...
Raffzahn's user avatar
  • 225k
1 vote

I need to find a controller card for an Apple II 5.25 inch floppy drive, the 20 pin connector wont work on the 34 pin controller card I have

actually, there was a 3rd party apple ][ card that would connect to standard 34 pin floppies. I had (should still have) one if no museums have this.
Carey Schug's user avatar

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