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31

For one, the II GS was the newer machine - providing a colour desktop and ADB before any Mac. From a user perspective GS/OS offered everything the Mac did. Plus compatibility with an uncountable amount of existing Apple II software. It was the long awaited upgrade for anyone (still) working with an Apple II - and there where many back then, while the Mac was ...


27

Fast Screen Refresh With PEI Slamming (Or: Dirty Tricks With the Direct Page) This article is based on my KansasFest 2004 presentation "Code Secrets of Wolf 3D." Introduction Drawing super high-resolution (SHR) graphics on the Apple IIgs is slow. Unfortunately, the SHR screen's memory in bank $E1 is located in "slow RAM" — that is, memory controlled by ...


16

That's an interesting and especially well prepared question. Thank you. AFAIR your second asumption is right. When shadowing is enabled for a region (see below) the CPU gets synchronized and slowed down to 1 MHz during the writing cycle for a clock period. This isn't as bad as it seams, since 'useful' RAM access (i.e. screen writing) is in average less ...


16

The "Control Your Apple ASIC" (CYA) was part of the "Apple IIGS 1 MB" introduced in 1989, which had 1.125 MB of DRAM and twice the ROM space of previous IIGS models. The CYA was much the same as the "Fast Processor Interface IC" (FPI) that earlier IIGS models had instead, and much of the technical documentation refers to either of the chips as the FPI. The ...


13

The memory shadowing feature copies writes from $01/2000-9FFF to the corresponding location in bank $E1. What you want to do looks like this: Perform computation for the current frame. Disable shadowing ($E0/C035 &= $F7). Render the frame into bank $01. Enable shadowing ($E0/C035 |= $08). Wait for the scan beam to reach a point where tearing won't be ...


13

The official ones, with GS/OS versions as indicated by the Apple II History site: Filename Purpose In GS/OS Version APPLESHARE.FST For AppleTalk networks 5.0 CHAR.FST Keyboard, screen, printers, and modems 4.0 DOS3.3.FST Apple II DOS 3.3 Disks (Read only) 6.0 HFS.FST Mac OS ...


12

Sounds quite like Tass Times in Tonetown. Although, IIRC it was about saving Grampa and the antagonist was a kind of a croc with several other besats mixed in 'man', but otherwise it fits. And yes, it was 'punky' :) It also had a remarkable user interface (that's why I remember it at all) combining the text based nature of classic adventures with a ...


11

The Macintosh sold for more because — as the shiny new thing — it could be sold for more. It was marketed as an aspirational product, not sold as a reasonable markup on an engineering BOM. The IIgs was about as far as you could go while keeping compatibility with the II range, and served as a useful cash cow funding Apple's Macintosh division for several ...


11

The largest amount of RAM supported by a real Apple IIgs is an 8MB expansion card, but that's somewhat misleading. The original IIgs came with 256KiB and the ROM3 came with 1MiB. A RAM expansion of 4MB will simply be added to these values. But when you have a card larger than 6MiB (which exists as well), you're going to see a problem: The extra RAM beyond ...


10

Keep in mind that because the memory in banks $E0 and $E1 are used as the 128K of memory in 8-bit mode (yeah, it's counterintuitive), they are controlled by the MEGA II chip, which is in essence an Apple IIe on a single chip (aside from processor and a few other support circuits). Any time access happens within the MEGA II's domain, the system has to slow to ...


10

The character set is known as "Mac OS Roman". The official mapping from Mac OS Roman to Unicode can be found on unicode.org. While the character set is similar to Windows-1252 and ISO-8859-1, having many characters in common, it's not a direct match for either. All of the characters are in the Basic Multilingual Plane (BMP). It's worth noting, however, ...


10

I suspect it was too late in the game for Infocom... The Apple II port of YZIP, Infocom’s Z6 interpreter, was released in 1989 (as far as I can determine), and by then Infocom was only a publishing house inside Activision, and was about to be shut down entirely. I imagine that, given the limited development resources available, Infocom would have preferred ...


9

The Apple IIgs Hardware reference explains it: In 640-pixel mode, color selection is more complicated. The 640 pixels in each horizontal line occupy 160 adjacent bytes of memory, each byte representing 4 pixels that appear side-by-side on the screen. The 16 colors in the palette are divided into four groups of 4 colors each. The first pixel in each ...


9

The bootprocess itself don't know any 'not bootable' exit. If a disk can be read, the first sector is loaded at 800 and then jumped to 801 (800 holds a counter for the number of sectors to read by the bootloader - usually 1). If there is no sector to be found, it spins indefinit. Non bootable disks may have some kind of error message, but don't have to. You ...


8

Your question conflates two questions into one: Did the IIgs sell more than the Mac in 1986? If so, why did the IIgs sell more than the Mac? Others have given valid reasons for (2), but there is evidence that the answer to (1) is "No". For instance this source says the Mac sold a million units by 1987, which is about what the IIgs sold over its whole ...


8

Generic answer, applies to any machine of a similar design in that condition: If you can, check the power supplies (not just for the machine preferably, on anything you are attempting to connect to it too!) with a load that you would not mind or manage to destroy (eg a set of power resistors). Do not test them completely unloaded! If you are proficient ...


8

From a more practical point of view, the program to convert between different character sets is called iconv. It can be used on the command line from the OS X (Mac) terminal, as well as in most Linux distributions. The most popular implementation is GNU libiconv, providing support for hundreds of different encodings, including MacRoman and the other Mac ...


8

In general, the IIgs was designed to have a full house in regards to expansion cards, just like every other member of the expansion slot Apple II family. There are guidelines for how much power a card can draw. However, there are not guidelines how how much heat a card can produce. Despite this, I'm not aware of any expansion cards from the era that produced ...


6

The CPU in the IIgs can address up to 16 megabytes of memory. Due to lack of address lines on the CPU chip, the upper 8 bits is sent out on the data bus before each memory access and is latched by external circuitry in the CYA/FPI chip. These 8 bits are referred to as 'Bank address'. Ahead of a memory access, the CYA chip will manipulate the timing, ...


6

According to the Apple IIgs Hardware Reference, Second Edition, page 49: The original Apple IIgs has 256K of RAM and 128K of ROM built in, and the 1 MB Apple IIgs has 1 MB RAM and 256K of ROM. This memory can be expanded to a total of 5 MB of RAM (4 MB RAM on a memory expansion card), and 1MB total ROM (768K ROM on a memory expansion card). Memory ...


5

In Neuromancer -- a 1988 game which was available on a variety of platforms including the Apple iiGS -- the player can sell their body parts for cash in the "Body Shop":


4

This might sound harsch to some people over protective of their little C64, but best practice is just doing - it with apropriate caution ofc. Always check the inside for obvious dirt, dust, rust and damage. Remove if any. Next plug it in and power it up (keep the lid/cover closed). If the machine has been stored in dry, clean condition, it should be fine ...


4

There was a big "Apple II Forever" push encouraging users to upgrade. Also schools likely bought IIgses in bulk for their computer labs, driving up the sales figures.


4

What is stored in the IIgs PRAM? Basicly everything you can set via the Control Panel I'm going to replace my PRAM battery in a ROM 03 IIgs and that got me thinking about what is stored in PRAM. I know that date and time are stored, but not if all the same values are stored on the IIgs as on the Macintosh. It's much like the Mac. In addition to things ...


4

You can replace with alkaline batteries, but will need a diode to prevent them being charged. Charging alkaline batteries, even very slowly, is risky and can cause them to leak. If the original battery is a 3.6V lithium cell. You could replace it with 3x NiMH cells which are 1.2V nominal each, and would be charged by the machine just fine. Use Eneloop or ...


4

What you need is a LocalTalk to Ethernet bridge. It's possible to use a computer for this but in general the most reliable and easiest path is to use a device made for this purpose. For example, I have a Shiva FastPath device that has a LocalTalk port and an Ethernet port. It will then transfer AppleTalk and IP traffic between them. If you only want ...


4

I might be wrong, but AFAIR it was something already present on the Apple IIc to support a 32 KiB ROM image instead of a 16 KiB (starting with ROM Version 0). For ROM access either half could be selected. So this isn't really A14, but the ROMs A14 to select one of two 16 KiB regions.


3

I'm using a Focus EtherLAN print box since many years for exactly that purpose with great success. It's small, reasonably fast, doesn't eat much power and it isn't restricted to only handle printers. Sometimes, the box would simply hang but a power cycle fixes this always. After I put the box from a normal switch port on it's own spare AppleTalk-only ...


3

Best way is to use a IIgs side utility to unpack disk archives onto real disks. First stop would be Sheppy's DiskMaker, a USD 5.- shareware utility, the gold standard here and youterpart to the original ImageMaker. Further there is Ninjaforce's ASIMOV utility, free of charge. Either should work as .2MG files are (*1) what's in the IIgs world called a '...


3

No, for writes to the extended ROM space, the IIgs ROM 01 FPI memory controller does not assert /CROMSEL. I assume it’s the same for the newer CYA memory controller chip in ROM 03 systems but I have not tested. Here are the logic analyzer traces. First is a read from F0/0000, in which /CROMSEL is asserted as expected: Next is a write to the same address, ...


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