John Elliott's DU54

[GeoffB17]

Further to the recent topic about creating a disk image on the PCW...


I have now got the DU54 system, and I've been playing with it.


Very interesting.   It goes a LONG way itself towards solving the initial problem regarding the disk images, and with the support of the 22DISK system, should sort the job completely.


DU54 allows the creation of a number of disk formats, and one is suitable as it gives a file capacity of 784k while still allowing auto-recog within the PCW system.   There are some other formats which allow more capacity, but they cause complications with the PCW recognising the format, and as the 784k one is big enough, it'll do the job.  I've made a disk of that capacity, and I'll make more for my own use.   That's nearly an extra 80k on the disk, with the format going from 9 sectors per track/side to 10.


The main function of DU54 modifies the normal COPY DISK process to include copy to FILE, and the file can be either RAW format, or CPC-type .DSK file.   It does NOT however allow for any sort of copy protection scheme.  This process will also include copy back from image to disk.   There is also a verify process, which is supposed to include the various extra formats allowed, but I was having a problem with that, so I'm not 100% sure?


So, can now create an image onto a floppy.


I've then checked the format details of the new disk, and created a 'format' within 22DISK, and got that working OK, so now the CP/M disk with the image on can be moved to a PC, and the image transferred there (either for safety, or for use in Joyce ?).   So, all OK.


Just been checking other formats for my own purposes, given I also use a 5.25" 40T drive, usually a 350k space.   Found there was a format giving me 384k, still auto-recog.   Not a LOT more, but enough to be useful, so I'll be making a few of them.   Again, mainly due to using 10 instead of 9 sectors.


All very useful, and interesting.  Thanks John.


Geoff

[TFM]

Hi! Where can we get the latest version?

[AMSDOS]

Hi! Where can we get the latest version?

In Here.

[GeoffB17]

I'm surprised there's anyone here who isn't familiar with John Elliott's site:


John Elliott's homepage


This starter page links to all manner of info about the Amstrad (and Spectrum) machines, and CP/M in general.  Much important technical info.  Should be one of your regular links.


I assume that the version of DU linked there is 'the most recent', but I cannot be sure?   It's the same one I've just started checking out.  Version 5.04, dated something like 1999, I think?


Geoff

[GeoffB17]

Further to this, I attach two files.


One is DU54.zip, this includes a 730k raw image of a disk with the DU54 system


The other file contains the DOS version of NSWP, for squeezing/unsqeezing.


Geoff