Remember SCSI? I certainly do. It was brilliant. But let me start at the beginning.
My first computer was an Atari ST. It was possible to connect hard drives to it. And they ‘just worked’. It was even possible to connect several hard drives at once, in a chain. Back then, I never knew how those things worked, but the poor suckers who ran DOS computers tended to find this fact impressive. My technical knowledge about Atari hard drives is still limited to the fact that they were comparable to jet engines with regard to the noise they made and that for some funny reason the 44MB Syquest was quieter than the 30MB driver which was quieter than the 20MB drive which, noisewise, could only be outperformed by high quality printing on our NEC P6 printer.
However, I have vaguely heard since that the interface that the Atari used was some kind of predecessor to SCSI, which was similar in many ways but not quite as powerful or so. It may have been called SASI, where I’ve no idea what the ‘A’ stands for.
After that I got my first Mac. It came with all bells and whistles, including a SCSI hard drive and that very wide port at the back. And it was perfect. Not only could I easily exchange the internal hard drive for a larger one when the need arose – I could also easily connect other people’s drives or the zip drive which I got at some stage.
And looking further than my LC III, I’d also like to note that even Nibbler, my SE comes with SCSI and will happily use and boot from my zip drive. Just think about it: A computer that was built in 1987 booting happily from a drive that was introduced in 1994. Compatibility won’t get much better than that. People keep saying that one of the biggest issued for Microsoft is (backwards) compatibility and that they spend a lot of money on it. I doubt that much was invested to make this work. It just does. Which in turn suggests that investing first to make up a solid standard like SCSI and then implementing it well will work much better with much less tweaking needed afterwards.
While this may be the ‘low end’ aspect of SCSI, I should remark that it worked equally well for more demanding tasks, like the Quadra I used during my civil service, which ran several hard drives, a tape drive, a Syquest, a CD drive, a scanner and whatever other hard or zip drives people brought along to bring data without a problem. And in my experience, SCSI was mostly flawless. Of course there were the two magic rules about the unique IDs and termination but, to be honest, sticking to them wasn’t rocket science. Rather trivial indeed.
In short, I was pretty happy with SCSI. Yet, luckily, I hadn’t invested too much in SCSI devices besides some hard drives and a zip drive, as – surprisingly – something better came along. Which of course was FireWire. My impression was that FireWire addressed all the obvious shortcomings of SCSI: The lack of well-defined hot-plugging, the easy but non-fool-proof manual settings, and the huge plugs. Those are user-friendlyness aspects only. Of course FireWire also offers a higher speed and – I suppose – one or two other technical niceties. Another non-obvious but rather cool feature of FireWire is that it can actually carry significant amounts of power – meaning that we can even power some devices right over the bus. Cool.
And Apple got a good start with FireWire. Well, they were among the first to include it on their machines, so that wasn’t too hard, I guess. But since then, the news have been quite mixed. I’ve heard of quite a few Apple machines that their FireWire performance isn’t as good as it should be and Apple is notoriously stingy with FireWire ports. My Powerbook (and all TiBooks and iBooks), for example, only has a single FireWire port.
With many devices that’s not a big deal as, similar to SCSI, FireWire lets you simply chain them up. But then there are also devices which only have a single socket and thus will terminate any FireWire chain. The most notable example for this is the iPod, of course. And it’s a pain. For a party, we wanted to connect two iPods to a single Powerbook to play songs from both of them. It wasn’t possible because of the lack of FireWire ports. So we had to fight to get the songs off the iPod, which due to Apple’s crappy support for that, was a royal pain. [I think this is a serious issue, btw, as there seems to be no user-friendly way to make a backup of a manually managed iPod.]
But there are two further issues, even with a single iPod. The first is that OSX is a pain in the ass when it comes to telling the user off for disconnecting some device. Most notably, again, the iPod. Why can’t I just grab the thing when I’m leaving but rather have to touch (perhaps even wake) the computer to convince it to let the iPod go first. It’s a device for carrying around after all. This is particularly bad for chains of FireWire devices and something where FireWire may actually turn out to be worse than SCSI.
While this certainly wasn’t recommended, with a chain of SCSI devices and a bit of luck you could remove, say, your zip drive from the middle of the chain and then re-connect the scanner at the end without the computer even noticing. With FireWire you’ll get an angry message. Can’t the computer at least suppress that if you happen to reconnect the device again? That’d make life a lot easier and less technical.
A final thing is an annoying fact that I discovered recently when Björn borrowed an external DVD writer. It’s a hell of a machine that probably beats my Powerbook in both weight and volume and that may be able to compete with the old Atari 30MB hard drive as far as noise levels are concerned. But, as both my Powerbook’s DVD drive mostly makes funny noises these days and, similarly, my external CD burner is acting up, I wanted to use the opportunity to burn some stuff painlessly (and use up the ‘wrong’ + or - kind of DVD-Rs that my dad had bought because Apple thought it’d be funny to ship computers that can only handle one of those and not put a big warning sticker on them).
So I connected the device into the existing chain of my CD-writer and iPod and then did some burning. No problems there (well, iTunes behaved like MSDOS in the 90s and decided to just not ‘see’ the burner, but thankfully I was more interested in doing backups). Everything worked fine, although my Powerbook (or its hard drive) make things rather slow when burning a DVD at 4x speed. After I was done, I thought I should shut off that noise, so I turned off the DVD burner. This usually worked in the SCSI days. I didn’t want to disconnect it as that would’ve run me into the FireWire chain problems I described above. But turning off the device broke the chain as well and the computer accused me of having disconnected stuff without asking first.
That’s bad. In particular as there clearly was a connection all the way through the chain at that stage – the iPod was still charging. Just the data part of the connection seemed to have been lost. So, reliability-wise, we’re back to the 1990s it seems. Sometimes things work and sometimes they don’t. That’s disappointing.
SASI stands for, if I remember right, “Shugart Associates Systems Interface”. (Checking acronymfinder, it looks like I’m right.)
There are FireWire hubs if you need extra ports; it’s not the perfect solution, but at least it’s reasonably doable.
Thanks for the acronym explanation, Christopher!
I know about FireWire hubs and even thought about getting one before. Mostly because of power problems. But in most situations, it just seems like a workaround that shouldn’t be necessary. And it costs money, of course.
I still don’t understand why my iPod will charge but not be detected when behind another device that’s turned off.
I’d have to guess that the other device passes the power signal along (or even energizes them itself when plugged in), but cuts the data lines.
Yeah, FW is certainly not perfect, but is overall a big improvement over SCSI. Before the iSight updater, for example, if I tried to sync my iPod with the iSight connected (even if it was off), it would transfer data incredibly slowly. Once the iSight was unplugged, the transfer would immediately speed up.
(This was, obviously, on a desktop machine with multiple ports, since neither device supports pass-through.)
Oh, as for getting songs off the iPod? As a long-time Unix user, I just cd into “/Volumes/podname/iPodControl/Music/” and use whatever set of Unix commands I feel like using to copy them to the hard drive. I suspect that copying the entire iPodControl tree would act as a complete backup.
As for the pass-through - I’d still wonder why any device should cut off pass-through when it’s turned off. That just doesn’t make sense for the user.
I am aware that it’s possible to copy stuff using the command line (I must have done that backup somehow…), but I don’t think this is an acceptable solution for a product sold by Apple. Things should be easy to use and the need for a backup is real (when sending the iPod in for a repair, say). While you and I may not have problems to get that backup done, I think that many iPod owners will have a real problem here.
And, as you say, Apple’s handling of FireWire in software doesn’t seem to be particularly good either. When I got my iPod, every time that I copied anything to the iPod the whole system would slow down a lot and the mouse cursor would ‘jump’ around rather than going smoothly. The problem went away after some system update, but I thought that just attaching and using a device shouldn’t affect the system in such a way.
Firewire deals with some of the short comings of SCSI, but not all of them. Firewire is a isochronous interface which is nice for multimedia transfer. And it doesn’t solve some of the other short comings (I must admit I don’t know how many device can be put on a firewire bus, but I am sure it is less than SSA or FCAL. Those two can deal much better with large configurations and are (mostly) self configuring and can deal much better with failures on the network. of course they have been designed with completly different problem set in mind, large storage arrays, while firewire is of course a multimedia interface.
Firewire supports up to 64 devices in a chain, Thomas ( I seem to remember that SCSI 1 supported 8 and SCSI 2 supported 16 ). SSA will give you 128 I think. The physical length of firewire chains can be much, much longer than SCSI, too. Something like 4 metres (or a bit more) between each device compared to a total chain length of under six meters for SCSI.
Sven, you probably could have got iTunes to recognise that DVD drive by using the excellent “Patchburn” utility - http://www.patchburn.de/
zip drives are pointless and gay !
Received data seems to be invalid. The wanted file does probably not exist or the guys at last.fm changed something.