This is very cool, love the effort on all of this to not use anything external but mostly I love the animations.
Thanks! Brian On Fri, Aug 20, 2021 at 9:38 PM Brian K. White <b.kenyo...@gmail.com> wrote: > > I've been working on this for a few weeks and I just hit the main > milestone that not only all the normal file access functions work, but > the FDC-mode functions work, including, dumping and restoring a whole > disk works. I just bootstrapped from a restore from a dump of a factory > tpdd1 utility disk. > > https://github.com/bkw777/pdd.sh > > > So, it's now possible to create a TPDD1 Utility Disk from a download, > with no exotic hardware, just the TPDD1 drive itself and serial > connection, and the software, aside from this script itself, is just bash. > > And the special challenge I set myself because I just knew it was > possible: It's not only all done just in bash, it's all done right in > the initial single process. No subshells, let alone external programs > like awk etc, not even tr/cp/rm etc, not even other instances of bash > from FOO=$(function... ). > > It's all in-memory ops and all in the single initial instance. > > Of course every absolute statement has to have exceptions... > It has to call "stty" once at startup, and it has to run "mkfifo" once > at startup if the fifo doesn't happen to be still lyng around from a > previous run. In both cases, the external doesn't constitute much of a > dependency because they are both so standard. I even addressed a pretty > wide range of platform differences for the stty command so it should > work out of the box on all the bsds, osx, as well as linux. And sine > they are just run once at start up, not many times in the middle of some > loop or in an aft-used function, they dont constitute an inefficiency > either. > > It was quite a challenge figuring out a way to collect, store, > manipulate, & reproduce binary data including NUL without resorting to > an external utility but there turns out to be a way to do it with read() > and a kind of brute force read-one-byte-at-a-time method where it is > possible to tell the difference between "the variable is empty because > there was no data", vs "the variable is empty because read() ate a nul > byte as a delimiter, by looking at the exit value from read(). That's > enough to let you store the information where the null byte existed, > which is all you need. to re-create it later in a file or tty. > > Then there is sleep that actually sleeps not a cpu eater poll, without > /usr/bin/sleep, and generally every bashism in the book. > > To be clear, my goal was to leverage bash for all it's worth, not to to > try for something like compatibility with ancient posix sh. The idea is > that bash is no longer new and exotic, and actually has a lot of > powerful tricks available built right in. It's possible to make actually > performant things in bash if you just do it right. Of course "do it > right" is pretty context sensitive. In order to satisfy the goal of > avoiding forks, you have to violate a lot of other good practices like, > this thing is a sea of global state and side effects. Fine, might as > well wallow in it then. > > And now that that's working well enough that a restore of the tpdd1 util > disk works, What I really wanted was to see if I could successfully copy > this Disk Power for KC-85 disk I have. This is a TPDD client for KC-85, > that I got a working original disk and tape with an ebay purchase , and > it turns out that it does not include a way to back itself up, and when > you try to back it up some other way using Floppy on a 100 or PDD210.EXE > in dosbox etc, the copy looks fine, but the install doesn't work. You > need both the cassette and the singular irreplaceable original disk to > install it, which is a situation I refuse to accept. ;) > > I *believe* I can now make a copy that's thorough enough thanks to the > FDC-mode functions, that the copy would work... and *just* when I > reached this point where I'm finally ready to try it... My KC-85 stops > working!!!! Well it's marginal. Sometimes it comes on and works, but if > I cold-reset, the screen goes blank and stays that way. "beep" doesn't > beep. > > Here a few pics of the Disk Power disk & tape. > > https://photos.app.goo.gl/YvPBJsYnP8N3JffW7 > > If anyone has a working KC-85 and wants to try it... you can get the > DiskPower disk dump here > https://drive.google.com/drive/folders/1HMZNi7S7O4s6Nn7sUcFVwrBVeVIFXSvA > > As well as the install file from the cassette. I think the install > program from the tape isn't as picky as the disk. As long as you get the > file onto the kc-85 by any method and run it while the drive is > connected and has the disk inside, I don't think it works. Not there is > a file with the same name on the disk, but it's a lot smaller and seems > to just be a stub or something. > > > -- > bkw >
