Depends on what "advantage" you're looking for. Once upon a weird history, there were some vinyl LPs made where you got two different music sets depending on which groove the needle dropped into -- and it was hard to pick either in advance as the record was turning. I admit that this is hard to arrange with floppies, since you need to count on _something_ being half a track off, and digital doesn't compromise the way analog does. Although with Flippies -- I tried them a few times when 5.25" SSSD were the standard at $30+ per ten-pack -- my failure rates were too high, much higher than when several years later I experimented with 35-track SSSD (rated) diskettes in 80-track DSQD drives -- I formatted over 50 diskettes rated for 86k in 720k drives and all were still readable more than five years later. Flippies had the problem that when you were reading the data from one side, the head-load pad or whatever was scraping off the data from the other side -- single-sided drives have little or no reason to be careful of the (supposedly unused) coating on the wrong side of the disc. Ward Griffiths "the timid die just like the daring; and if you don't take the plunge then you'll just take the fall" Michael Longcor On Fri, 22 Jan 1999, Tony Duell wrote:

I can guarantee that no 80-track drive was ever officially supported in a Model 4 or any other Tandy Z-80 platform, no matter what the documentation might have implied once TRSDOS-6 (and LDOS) became official products. That's like letting on that OS-9 Level One could be used by more than one person on the same 64k TRS-80 Color Computer the way I demonstrated in my classroom in the Radio Shack Computer in downtown Los Angeles back in 1984. (Or was that late '83? Damn, this senility is a bitch to deal with -- the AT was still vapourware). Ward Griffiths "the timid die just like the daring; and if you don't take the plunge then you'll just take the fall" Michael Longcor On Fri, 22 Jan 1999, Tony Duell wrote:

On Fri, 22 Jan 1999, Tony Duell wrote: Under the Z-80? All of the plans for putting in a Dallas clock chip that I ever saw stuck it under the BASIC (or boot in the 4P's case) ROM. Naturally. The Model 4 was a great design. (The Model 2 was better, but it didn't need to be backward compatible). I set up a multi-user system in my classroom in the Radio Shack Computer Center in downtown Los Angeles with a 64k CoCo with one floppy and OS-9 on one end and a 16k CoCo with a Vidtex ROM at the other end of a kluged null-modem cable between the bit-banger ports. I was being facetious in my previous comment, honest. The company of course never supported the configuration. That was before the official RS-232 Pak, so of course the system couldn't print and due to poor handshaking between the bit-banger ports, the "terminal" tended to drop characters if you typed during a floppy access. After a change of managers, I didn't get a chance to redo the system with better serial connection and a hard disk, the new guy wasn't as cooperative. He thought it would trivialize Xenix or something. Bastard. As though I'd risk trivializing my greatest love at the time -- I knew the difference between a 6809 and a 68k. By the time OS-9 Level 2 showed up, I was always up to my ass in alligators anyway with the damned Tandy 1000 and its constant demands for tech support. I've got a couple of two and three port RS-232 cartridges here for my CoCo 3 systems and their hard disks. If the cablemodem works as it's supposed to, in not too many weeks it'll be possible for guests to telnet into my Linux box and get a serial login to OS-9 Level 2 as well as Tandy 6000 Xenix (after I figure out why it doesn't want to talk to the hard disk) an AT&T 7300 and possibly a few other things. Assuming that La Esposa permits me to use that much electricity at a time. I may have to rotate things on a schedule or something. -- Ward Griffiths "the timid die just like the daring; and if you don't take the plunge then you'll just take the fall" Michael Longcor

On Fri, 22 Jan 1999, Tony Duell wrote: What the CP/Mers used to refer to as Quad Density. Don't know, Tony. All I can suggest is to degauss them first, but you probably do that anyway. - don