Re: Floppy disk bootloader, now with Twiggy support

>I've updated my public domain Lisa floppy disk bootloader to include
>support for Twiggy disks.

It is interesting to watch where you are going with this!

>disk media type is controlled by source code configuration options
>(unlike e.g. whatever code bootloads BLU)

I have to admit that the BLU loader "cheats" by knowing that it is not on an 800k disk, and therefore is less than 400k, so it always will fit on the first side of a Twiggy. As a result, the loader doesn't need ever use the second side of a disk.

Removing the side-select logic makes it easier to fit in one sector -- it simply selects the sectors/track table depending on the drive type (as indicated by the I/O Board ROM ID).

If a "universal" loader cannot be optimized to fit in one sector, one could use a two stage loader; a universal loader will certainly fit on the first side of the first track, and that can be loaded using the BLU strategy. I suspect that would be enough room to make it a multi-disk loader too.

James

-- 
-- 
-----
You received this message because you are a member of the LisaList group.
The group FAQ is at http://lowendmac.com/lists/lisa.html
To post to this group, send email to lisalist_at_email.domain.hidden
To leave this group, send email to lisalist+unsubscribe_at_email.domain.hidden
For more options, visit this group at http://groups.google.com/group/lisalist
--- 
You received this message because you are subscribed to the Google Groups "LisaList" group.
To unsubscribe from this group and stop receiving emails from it, send an email to lisalist+unsubscribe_at_googlegroups.com.
For more options, visit https://groups.google.com/d/optout.