Questions and Answers
Copyright (c) 1995 Apple Users' Group, Sydney
Republished from Applecations, a publication of the Apple Users' Group, Sydney, Australia.
Source: comp.sys.apple2
Q: What does the Alternate Display Mode CDA do?
A: In the Apple II display modes (40/80 col text, LoRes Graphics, Hires (280x192) and Double Hires (560x192) graphics, plus mixed modes), each possible mode has 2 'pages' that can be displayed. Thus, a program can display one screen, draw on the other, display that, and work on the first.
Anyhow, in the GS emulation of the Apple II modes, almost all modes are handled normally by the hardware. But, the second text screen (not really used very much at all) isn't displayed this way. Therefore, the few programs that tried to use this screen mode wouldn't work, putting up a screen full of garbage, usually '2's.
That's where the Alternate Display Mode comes from. It sets up a background task to copy the page to the memory where it's displayed from so it looks right. If you must view this display area, it's a real useful tool. If you're like the 99% of us who never have any cause to use it, it's an extra entry in the CDA menu, and eats system time when on.
Q: Does anyone know of a good Freeware or Commercial Menu Program for the IIgs running System 6.0.1? It needs to be Dummy Proof. Basically I want to make a menu to allow young kids to run games, applications, etc with a single click.
A: Try Utility Launch by Geore Wilde. It's great for kids. It's exactly what you describe: big buttons that take a single click to launch. It is very customisable, too. A commercial solution exists in the form of
WINGZ from Vitesse software. ProDOS 8 based program selectors include SNEEZE (freeware) or ProSEL (commercial).
Q: I still don't know how the GS figures out how much memory
is installed. Can anybody explain this?
A: The routine that determines the size of the IIgs's memory is called during the first MMBootInit call after a cold start. On Control-Apple-Reset, or power up, the reset code calls TLBootInit, which calls MMBootInit and the other BootInit calls.
There is a flag which is set after the first call has been made, so this routine won't be called again until the computer is turned off, the RAM disk is resized (Resize after Reset option - ROM 03 only), or the self test is invoked.
The memory size routine writes a two byte value to locations $0000 and $0001 in every bank, starting at bank $7F and working down to $02. The value written starts at $FF80 and climbs to $FFFD as the bank decreases. Note that the sum of the number written and the bank number is always $FFFF.
After writing all these values, the memory manager scans through them again, starting at the top and working down, until it finds an entry that has the correct value. It uses this as the 'highest valid bank number', which is stored in a couple of places in bank $E1 for future reference.
Most memory cards will cause 'echoes' to appear. For example, Apple's IIgs Memory Expansion card with 1MB installed appears in banks $02-$11 on a ROM 01. There will also be an echo of the card in banks $12-$21, $22-$31, etc.
This means that location $12/0000 appears to contain RAM, but any value written to it will also appear in location $02/0000. The same happens with most 4 megabyte cards, in both ROM 01 and ROM 03.
The memory size routine takes care of this echoing effect because if there was an echo, the last value written to the RAM would be the number of the LOWER bank, and the higher bank's number wouldn't match.
For example, if a 1MB card was installed in a ROM 01, the value written to $12/0000 would be $FFED, and the value written to $02/0000 would be $FFFD. When reading back from $12/0000, the memory manager would see $FFFD (because of the memory echo) and would not regard bank $12 as a valid part of memory.
The problem with certain memory cards not supporting three rows of RAM chips arises because they leave 'holes' in the IIgs memory map - once the memory manager finds something that looks like valid RAM, it assumes everything below that point is available.
Q: I want to print some old Apple //e HGR Hi-Res graphics on my Macintosh. Is there any way to convert the Apple format into something for the Macintosh?
A: If you have access to an Apple IIgs, Roger Wagner's The Graphics Exchange does a wonderful job converting graphics between Apple II and Macintosh formats. SHR Convert, and Seven Hills' SuperConvert will also do the job.
On the Macintosh side there is a program called Imagery that reads Apple IIgs formats. Alternatively, you could run STM, an Apple II emulator, on the Macintosh and use Shift-Command-3 to capture screenshots. You can then cut and paste right into whatever Mac application you are using.
Another commercial Macintosh program is DeBabelizer which converts any graphics format to any other graphics format. It does support many Apple II formats (although it can't figure out what type of data is in each file, you have to tell it "This is an HGR file, this is a Paintworks SHR file, etc.).
The full version of DeBabelizer is a expensive, however, there's also a package called DeBabelizer Lite which is less expensive. It may not include the Apple II translations, however.
Q: Are power supply problems, such as over heating and lack of 'juice', common problems with power users? My original power supply blew up several years ago, so I'm currently using one from a ROM 1 GS. Should I just invest in a heavy-duty power supply? What about internal fans?
A: Apple's IIgs internal power supply is inadequate for any seriously beefed up system. It doesn't supply enough current and there aren't enough air holes to adequately cool the thing anyway, so once you start abusing it it will start to heat up which makes it deteriorate even faster.
The internal fan sold by Apple sucks!! I am sorry I bought one. It is too loud and blocks slots 1, 2, 3 from having any usefully long cards in them. (Just like Pentium heat sinks in many PC's, BTW.)
I heartily recommend both the Jameco and JDR replacement power supplies and the Kensington System Saver IIgs, if you can find any of them these days...
Q: I've just heard about something called a bluedisk controller card. Can someone explain what this is?
A: The BlueDisk controller card enables you to use two IBM PC compatible floppy disk drives on an Apple //e or IIgs. The drives can be 5.25" or 3.5" and any capacity up to 2.88MB. To get more info, email the maker: jlange@tasha.muc.de
Q: I'm looking for the requirements to connect a newer DeskJet (520, 540, 560) to an Apple IIGS. They only have the DB-25 connector. What card and/or cable would this require?
A: I'm running a DeskJet 540 from an Apple Parallel Card, but any parallel card which is supported by one of the GS/OS parallel drivers will probably do. Once you've installed the parallel card in a slot (usually slot 1) you'll need to change the Control Panel setting for Slot 1 to "Your Card".
I have actually installed my Apple Parallel card in slot 2, keeping my ImageWriter II connected to the Printer Port. With Slot 2 set to "Your Card", and with a modem connected to the Modem Port, I can run ProTERM and actually capture email to the DeskJet while online!
Q: I'm having a few problems with my DJ 500C and Harmonie. Whenever I try to print at 300 DPI the fonts print very small. The happens on the first page. I have the dip switch set for 300 dpi. I have been working on some business cards in GS III, and I'm using a 24 or 38 point font. The font that prints is microscopic, I can make out that it says what it is supposed to but it is way too small. If I change the resolution in Harmonie to 150 dpi, It prints ok, but the I loose some quality.
A: I don't know how the dip switches work on the DJ 500, but I'm using a DJ 540 with Harmonie, and I know that if I set the PAGE SETUP of a document to 300x300 DPI, I get microscopic printing, but if I PRINT at 300x300 DPI I get wonderful results. I leave the Page Setup at 'DeskJet Best' which is 75x75 DPI.
Q: I've used the DeskWriter C from my GS with the Harmonie drivers. Works great, but, as mentioned, DeskWriters only work from GS/OS, DeskJets have built-in fonts that also let you use them from ProDOS 8. The same printer driver is used for both the DeskWriter and DeskJet.
A: Not quite... The DeskWriter has the same internal fonts that the DeskJet has, but the reason it is not easily accessible from ProDOS 8 is that its serial port is locked at 57.6Kbaud, so the firmware can't drive it. With special code to run the serial port at the required speed, you can print just fine. (Fire up any telecom program that can do 57.6K on the IIgs and try typing to the port to which the printer is connected. Hit CTRL-L to get the page out. It may be a bit messy, but it does work.)
I have printed successfully to a DW-C on AppleTalk from AppleWorks by printing to slot 7. The trick is that I had to modify the Network Printer control panel to get it to see the DeskWriter first. I haven't had time to go back and clean up the patch into any sort of distributable form, but I hope to get back to it after I finish my current project.

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