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I believe that some versions of the Delta controller where single density only. Dragon / Cumana /Super DOS where double density, from what I remember vcopy only deals with double density disks. If you have access to a DOS PC (Win 95/98 might work, if you boot into dos only), you could try analysing ...

You could do the memory remap the way that the Dragon Beta/128 did it. Use a RAM chip such that you feed the top address lines into the chip and use the data lines out of the chip to generate the top address to the main RAM. So : A15..12 on the 6809 connect to A0..3 on the RAM, then A4..7 of the RAM...

Of the 4 Alpha boards I have seen, all have been exactly the same with just the version of the BIOS changing (2 versions known and dumped) I believe the Alpha I have has a slightly earlier version of the board, I think issue 1 and the others are issue 2, I'll verify when I get home from the Acorn m...

If you where going to attempt it, it would be better IMHO to try and adapt to 9x512 byte sectors. Whilst the 2797 is capable of reading a HD disk, you would need to firstly modify the DOS controller to run the 2797 with a clock of 2MHz, and secondly you'd need to run any code accessing the floppy fr...

I'll take some piccies and post later this evening...... I'm working on an RGB interface for the Acorn Atom (which also uses the 6847), I've got that pretty much working so I tried putting one of the boards in a Dragon, as I had one with a socketed 6847 and have that working pretty well. It decodes ...

And 64K is worth having, of course :) Looks like you got one with the improved keyboard, too. Didn't all 64s have the metal plated keyboard with the clipped in keys ? Actually my original 32 did as well, which is why I never understood people's gripes about the 32 keyboard until I got another 32. C...

It's just struck me whilst looking at the Dragon 64 circuit diagram, that the board was obviously an improvement as it's included in the Dragon 64 circuitry (IC14 & IC13A). Just looking to maybe try and convert my Atom RGB board to work on the Dragon & CoCo, would not be a problem if the 6847 was so...

From BASIC the smallest unit you can read is a sector into two 128 byte strings, as robcfg points out. The trick is to figure out which sector to read. If you are willing to use machine code, there is a ROM routine to read raw data from a file. See the READ routine located at [$C014] documented in ...

Nope you can't swap the power boards, as the connecting cable between the power board and the Tano mainboard is wired slightly differently. If you made an adapter cable it might be possible, I did this with a spare tano board I had so I could use it in a spare 32 case, but from what I remember I was...

Looks like a fairly standard external character rom circuit, there's details in the full version of the 6847 datasheet.

Cheers.

Phill.