Autoboot for floppydisk

A place to discuss everything Dragon related that doesn't fall into the other categories.
Post Reply
Posts: 2
Joined: Mon Dec 30, 2019 9:39 pm

Autoboot for floppydisk

Post by redblueflame » Mon Dec 30, 2019 10:13 pm

Hi everyone !

To raise awareness in the Dragon 32/64, I'm currently trying to auto boot floppy that aren't bootable.
After some days, I have only three solutions:
  • Making a list of .bin names for each software and game available in this format (This is by far the longest solution)
  • Implementing the DIR routine from DOS in the host system to get the name of the file (I think this is the hardest solution)
  • Finding a way to do it on the DOS side, with a basic program, or a machine code one. For basic, afaik it seems impossible to interface with the DIR command, to get a list of files or a string with the result of the command.
As you can see, I don't have any great and easy solution.
So after all this background, is it possible to interface with the DIR command, with a specific DOS or a .bin file ?
Thanks in advance,

Posts: 61
Joined: Wed Sep 07, 2016 4:45 pm

Re: Autoboot for floppydisk

Post by bluearcus » Tue Dec 31, 2019 3:28 pm

Hi RedBlueFlame,

Reading the directory entries can be done from BASIC by getting raw disk sectors in the directory area using the DragonDOS sector read commands.

SREAD is the command, and it takes a drive number, track number and sector number, and two string variables as parameter:

SREAD 1,20,3,S1$,S2$

it drops the specified sector into two strings, each 128 characters in length.

Information on the disk format can be found here:

That should be enough to get you some directory information out into your menu program. Autobooting (rather than running a selected program) is a different matter. There are some threads on that here I think and on the Facebook group.

Kind regards,


Posts: 1351
Joined: Sun Mar 25, 2012 7:32 pm
Location: Barcelona (SPAIN)

Re: Autoboot for floppydisk

Post by pser1 » Thu Jan 02, 2020 3:55 pm

if you want a disk to autoboot, that is autostart a program, then you need to use a DOS that offers this feature
else you will need to issue the command BOOT instead. Right now I just remember the Eurohard DOS4.1 having that feature

Next step will be saving the program you want to be autostarted on a disk. You could then use a program that will write into the
boot area, in sector 3 (just using 256 bytes). The program I am talking about can start from the boot area any basic program
as well as any binary file.
Not sure if it is in the archive, so I am attaching here a zip file that contains an VDK with the basic program that does the trick,
I hope this could be of help!

BOOT v1.1 (1985)(MHSoft).zip
(1.48 KiB) Downloaded 36 times

Post Reply