Newsgroups: comp.sys.apple2 Path: news.uiowa.edu!news.physics.uiowa.edu!math.ohio-state.edu!howland.reston.ans.net!newsfeed.internetmci.com!news.msfc.nasa.gov!pendragon!ames!waikato!comp.vuw.ac.nz!actrix.gen.nz!dempson From: dempson@atlantis.actrix.gen.nz (David Empson) Subject: Re: Appletalk and IIGS Message-ID: Sender: news@actrix.gen.nz (System Administrator) Organization: Actrix - Internet Services Date: Sun, 7 Jan 1996 00:43:23 GMT References: <4cj9sn$5mm@yama.mcc.ac.uk> X-Nntp-Posting-Host: atlantis.actrix.gen.nz Lines: 60 In article <4cj9sn$5mm@yama.mcc.ac.uk>, Duncan Entwisle wrote: > In the control panel the Apple IIGS claims to have built in appletalk > (although this doesn't have a tick next to it - whatever that means) The ticks in the control panel are used to indicate the default setting (if you use the "restore default settings and 50 Hz" or "... 60 Hz" options in the Control-Option-Reset menu, or the battery RAM loses its contents). The IIgs does have built-in hardware support for AppleTalk (LocalTalk), using either the Printer or Modem port. In the ROM 1 IIgs, you must set either of slot 1 or 2 to "Your Card" and set slot 7 to "AppleTalk". The AppleTalk connection will then make use of whichever of slot 1 or 2 is set to "Your Card". (If both, then the Printer port will be used.) In the ROM 3 IIgs, you must set either of slot 1 or 2 to "AppleTalk". Slot 7 also has an "AppleTalk" option, but this is only there for compatibility with brain-dead programs that assume the IIgs AppleTalk support is accessed via slot 7, and enabling it will waste a slot. On the firmware side, the ROM contains enough code to allow the IIgs to boot from an AppleShare server, but the full set of AppleTalk protocols is only available after booting in this fashion, or by booting from a local system disk that has AppleTalk support installed. If booting from a local disk, you must boot via GS/OS to be able to get full AppleTalk support. (There is a file which doesn't seem to have been widely released which allows printer-only access when you boot ProDOS-8 directly.) > can this only be accessed by extra software, or could I use it to boot > from my Mac (is that possible - would it require extra software on the > Mac side too) - as this would save me buying a 3.5 inch disc drive. You can only boot from a Macintosh that is running the full AppleShare server software, version 2.x (takes over the whole machine and runs under System 6) or 3.x (other programs can be run at the same time, requires System 7). Version 4.0 and later do not support network booting for an Apple II. With the File Sharing support provided by System 7, you can log onto the Mac from the IIgs after booting from a local disk, but you cannot boot from the Mac. Even with the full AppleShare software (which is very expensive), you will still need a 3.5" drive, as you have to install the necessary software onto the server from a IIgs. I wouldn't recommend just borrowing a drive - you will be able to do very little with a IIgs connected to a server which doesn't have a 3.5" drive, as you won't be able to install any new software, for example. -- David Empson dempson@actrix.gen.nz Snail mail: P.O. Box 27-103, Wellington, New Zealand Dennis Jenkins wrote: > Is there a FAQ about the IIgs that can answer all of my questions > listed below? Yes, me. :-) > I finally got an ADB cable so I can use me IIgs and Mac-LC II. This comment suggests that you might be trying to plug both computers into the same Apple Desktop Bus at the same time. If so, don't! > After paying attention (it helps sometimes) to the IIgs, I have learned > that it is indeed a ROM01 in a 'woz' case. Yippie for me? Yes, that is good news. It means you will be able to run the latest IIgs System Software (6.0.1), given enough RAM. > Anyway, I was playing around in the control panel and noticed that I can > toggle slot #7 from 'user card' to 'appletalk', but only if I turn off the > modem and/or the printer. I've never had a IIgs before, and I have no > books on one, so I didn't know exactly what this could do for me (I'm a unix > guy, but I've heard of Appletalk. It is just a network implementation > that runs on top of IEEE 802.3, right?) Not exactly. AppleTalk is a protocol stack similar in principle to TCP/IP or Netware, i.e. a suite of related protocols. AppleTalk was originally implemented on the Mac 512 (and 128?) and early Apple Laser printers, using serial ports running in bit-synchronous (SDLC) mode at 230400 bps. You can connect up to 31 devices together using a drop box that plugs into the serial port of each device. A cable is then run from one drop box to the next one, forming a daisy chain. The network is half duplex, and transfers data about the same speed as a floppy drive. Some time after its original implementation, Apple introduced additional hardware capabilities for AppleTalk, including Ethernet support. At this point, they coined the name "LocalTalk" for the original implementation via the serial port, and use "EtherTalk" and "TokenTalk" when referring to AppleTalk over Ethernet or Token Ring. There are various bridging and routing options for connecting the different types of networks together, forming what is confusingly called an "AppleTalk internet". Using current terminology, "AppleTalk" means the protocol stack, and "LocalTalk" refers to AppleTalk running over serial ports, and to Apple's physical cabling system. There is also a third-party cabling system based on telephone cable, usually called "PhoneNet"; it doesn't require any special software, and as far as each device is concerned it is running over standard LocalTalk cabling. In most cases, you can connect two LocalTalk devices directly to each other using a normal (Mac) serial cable. You only require the drop boxes and special cabling if you want to connect at least three devices. The IIgs has built-in support for AppleTalk running over LocalTalk (or PhoneNet) cabling. The ROM contains enough code to allow the machine to boot over the network from a Mac running AppleShare 2.0 or 3.0 with Apple II boot support (this feature was removed in later versions of the AppleShare server, and is not provided by the Mac's built-in File Sharing). GS/OS also has support for logging on to an AppleShare (or File Sharing, or compatible) file server, and can access ImageWriter II, ImageWriter LQ and LaserWriter printers over an AppleTalk network. The file sharing client support requires that the server can deliver AppleShare over the AppleTalk protocol stack. Apple introduced suport for AppleShare over TCP/IP a few years ago, but this is not supported by the IIgs. If you have booted GS/OS with the appropriate AppleTalk support code, then you can also access file servers and network printers under ProDOS-8. If you boot ProDOS-8 directly, you cannot access network file servers, but there is some software which provides network printer support. There is no support for using the IIgs as a server for File Sharing, only a client. As far as the slot settings are concerned: On the ROM 00 or 01 IIgs, you must set slot 7 to "AppleTalk" instead of "Your Card". In addition, you must set either slot 1 or 2 to "Your Card" instead of "Printer Port" or "Modem Port". The LocalTalk network must be plugged into the port corresponding to whichever of slots 1 or 2 are set to "Your Card". (If both are set to "Your Card" and slot 7 is set to "AppleTalk", then the printer port is used for AppleTalk.) On the ROM 3 IIgs, you can set slot 1 or 2 to "AppleTalk" directly, and can use slot 7 for your own card. > My linux box can do Appletalk. netatalk or an equivalent, I assume? There are a couple of problems getting the IIgs to talk to this: - Physically, you need a LocalTalk card in the PC, or an AppleTalk bridge/router between Ethernet and LocalTalk. - I think some patches are required to allow netatalk to support an Apple II client (possibly issues with the authentication method supported for logging on to the server?) > What OS on the IIgs do I need to accomplish this? The best option is to run System 6.0.1 from a hard drive on the IIgs, with the appropriate AppleTalk support code installed. You can do it from a floppy, but only by removing parts of the normal system software, including the Finder. This makes it rather difficult to use. Booting from a Mac running the AppleShare server is another option (albeit a slow one). > My IIgs has 2 5.25" floppy drives (ie, the drives that I swap back and forth > between the IIgs and IIe). Oh dear. You will need a 3.5" drive (preferably an Apple 3.5 Drive) to be able to run GS/OS. You cannot boot GS/OS from a 5.25" drive. Better still, get a hard drive (and appropriate controller card) as well, since that makes the IIgs much more usable. In addition, you will need a reasonable memory expansion card if you don't have one. If you aren't sure what you have right now, go into the Control Panel and have a look at the "Largest Selectable" value for the RAM disk. This will tell you how much RAM is installed in your memory expansion slot. (For anyone else who has a ROM 3, the calculation isn't quite this simple: subtract 896 KB to allow for the extra RAM on the motherboard.) To be able to use GS/OS, you need a minimum of 1 MB of available RAM, i.e. a 1 MB memory expansion card in a ROM 1 IIgs. If you want to use AppleTalk networking, you are likely to need a little more than this. In any case, the best option would be a 4 MB or larger memory expansion card, since this gives you a lot more flexibility. > Also, what is the 'smart-port' device on slot #5? I have heard people > on this group talk about it, but they already know what it is, so they > don't bother to elaborate on it. What can I do with this device? "SmartPort" refers to four different things: 1. The disk port on the back of the machine, when it is being used to communicate with 3.5" drives. 2. The slot 5 firmware in the IIgs, which controls the disk port for 3.5" drives and also provides support for the RAM disk and ROM disk. 3. The API used by this firmware and by other I/O cards (such as Apple's SCSI cards and some standard slot memory expansion cards), which allows up to 127 logical devices to be accessed, and provides support for large block devices and for character devices, with the ability to identify the types of devices connected. 4. The protocol used to communicate between an Apple II and intelligent devices like the UniDisk 3.5 (via the disk port). If you set slot 5 to "Smart Port", you are enabling the internal firmware (item 2), allowing you to connect 3.5" drives to the disk port, and use the internal RAM disk. Slot 6 also has a "Disk Port" setting. This enables the internal firmware which provides support for 5.25" drives connect to the disk port. (If you are connecting both 5.25" and 3.5" drives to the disk port, you must connect the 3.5" drives first, then the 5.25" drives daisy chained to them.) > What does 'enable alternate video output' do. I toggle it back and > forth and notice nothing. My IIgs is connected to my Apple Color > Composite Monitor via a RCA cable. I'm not aware of anything with this name. Perhaps you mean "Alternate Display Mode", which is a separate item in the Desk Accessory menu? Alternate Display Mode lets you enable or disable support for a rarely used video display mode on the Apple II: text page 2. This gets a little technical, so bear with me. The IIgs is a hybrid machine, sort of like a cross between an 8-bit Apple II and a 16-bit computer. There are several aspects of the 8-bit side of the machine that are implemented by a chip called the "Mega II", which is effectively an Apple IIe/IIc on a chip (minus CPU and memory). The 16-bit side of the machine is mostly implemented by a chip called the FPI ("Fast Processor Interface"), which is replaced by a chip called the CYA (speculated to mean "Control Your Apple") on the ROM 3 IIgs. The most noticeable aspect of the 8-bit and 16-bit split is the way the memory is organised. RAM in the IIgs is divided into two areas: - "Fast" memory starts at bank $00 and can go as far as bank $7F. This memory is controlled by the FPI. On a ROM 00 or 01 IIgs, banks $00 and $01 are on the motherboard, and the rest can be provided by the memory expansion slot. ROM 3 has banks $00 to $0F on the motherboard. - "Slow" memory occupies banks $E0 and $E1. This memory is controlled by the Mega II. "Fast" memory is able to run at the full speed of the IIgs, i.e. 2.8 MHz, except that the FPI must perform refresh cycles. This slows down the average speed to about 2.6 MHz. In addition, if you have set the system speed to "Normal" in the control panel (or software does this), then "Fast" memory will be accessed at the normal speed of an Apple II, about 1.027 MHz (with no overhead for refreshing). "Slow" memory always runs at the original Apple II speed, about 1.027 MHz. If the Control Panel is set to "Fast" speed, then the FPI has to synchronize with the Mega II to allow the CPU to access the slow memory areas. There is also ROM, which lives in banks $FE and $FF for ROM 00/01 ($FC to $FF for ROM 3). This is able to run at "fast" speed, and doesn't suffer from refreshing overhead. The "slow" memory banks look just like a 128 KB Apple IIe: RAM from $0000 to $BFFF, I/O space in $C000-$CFFF, and languge-card style RAM in $D000-$FFFF, with main and auxiliary memory mirroring the RAM. The video buffers are all in "slow" memory: $0400-$07FF is text or lo-res graphics page 1, $0800-$0BFF is text or lo-res graphics page 2, $2000-$3FFF is hi-res graphics page 1 and $4000-$5FFF is hi-res graphics page 2. Bank $E0 is main memory, which contains the 40-column video buffers, and bank $E1 is auxiliary memory, which contains the second half (alternating columns) of the 80-column video buffers. In addition, the IIgs has a new graphics mode called Super hi-res. This is implemented by the VGC (Video Graphics Controller), and it uses the memory area $2000-$9FFF in bank $E1 as its video buffer. It only has a single display page. The "fast" memory banks are a much cleaner arrangement. In their native state, they are pure RAM from $0000 to $FFFF. There are no bank switching tricks to worry about, and the IIgs is able to treat its "fast" memory area as a single linear address range, except for some details of the processor that impose a 64 KB bank structure on it. This would all be fine if the IIgs only ever ran a native operating system, but in order to maintain compatibility with 8-bit software, it must emulate an 8-bit Apple II to some extent. To allow this, the IIgs has soft switches which change the layout of banks $00 and $01 to mimic an 8-bit Apple II, i.e. $0000-$BFFF are RAM, $C000-$CFFF are I/O and $D000-$FFFF are language card RAM or ROM, with bank $00 being main memory and bank $01 being auxiliary memory. This is how the IIgs normally runs - very little software ever turns off these features to make bank $00 and $01 look like 64 KB of RAM. Note that banks $02 through $7F are not affected - they are always viewed as 64 KB of RAM per bank. Now we run into the problem with the video buffers. They are physically located in banks $E0 and $E1, but software expects to find them in the nominal main and auxiliary memory banks $00 and $01. To support this, the IIgs provides "shadowing" features, which can be enabled separately for most of the video buffers. When shadowing is enabled, a write to the appropriate memory area in bank $00 or $01 will cause a simultaneous write to the actual video buffer in bank $E0 or $E1 (and it is forced to run at "slow" speed). A read from the memory area in bank $00 or $01 is not affected by shadowing (so it can run at "fast" speed). Shadowing is almost always enabled for the text screen, and is usually enabled for the hi-res graphics screens when running 8-bit software. When running native IIgs software, shadowing is usually enabled for the super hi-res graphics screen, but not for the normal hi-res and double hi-res graphics screens. So, what exactly is the story with Alternate Display Mode? Text page 2 was so rarely used by software that Apple decided not to include hardware support for shadowing of this memory area in the original IIgs (ROM 00 and 01). To allow for the few cases where it was needed, they provided the Alternate Display Mode classic desk accessory, which can be used to turn on or off a software emulation of shadowing. If Alternate Display Mode is enabled, the IIgs has a timer interrupt running which copies the contents of memory locations $0800-$0BFF from bank $00 to bank $E0 several times a second. This causes a noticeable performance hit, so you should never turn it on unless you are running software that needs text page 2. You can usually tell that you need to turn on Alternate Display Mode if you see a text screeen filled with "2" characters (this is the default contents of the real text page 2 in bank $E0 when the machine starts up). With the ROM 3 IIgs, Apple implemented hardware support for shadowing of text page 2. The ROM 3 still has an Alternate Display Mode desk accessory, but all it does is enable or disable the hardware shadowing feature. Since the $0800-$0BFF area is frequently used for purposes other than a text display, it is still a good idea to leave Alternate Display Mode off unless you need it for a particular program, because the shadowed copying of memory writes in this area would cause a slight performance degredation.