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Thanks to all for information. I wish I could try multiple readings to correct errors but it won't be easy: - the unsynchronised bytes at the beginning and the end will probably differ at each reading - the $C2 inserted here and there lead to a track size that changes, so comparing byte for byte won...

That's surprising to use 0x4E as a sync byte 0x4E == 0b01001110 which does not seems a good sync byte.. Anyway, the Oric 0x16 is not "good" either :D (0b00010110) Why they didn't use 0xAA (0b10101010) or 0x55 (0b01010101) or a mix of both for sync? It will be easier to sync with a regular...

Symoon wrote:For my culture, the FDC doc talks about an "AM" the chip is waiting for... What's an "AM"?

Found it in Sedoric à Nu: Address Mark. Not sure what it is exactly yet, but at least I know what it means

Thanks for all the replies guys ;) Also, if the floppy have some defect, it is possible that the hardware try to resync (the $c2) Well I tested 2 different controllers (mine and NightBird's one), 3 drives (including 3" or 3.5") and about 5 or 6 different disks. On each test I read the same...

It would be interesting to adapt your program to the Jasmin controller and see if there is the same problem. Are there any technical docs for FT-DOS, just like l'Oric à Nu for Sedoric? I've never been an ASM expert and it always takes me ages to understand rough code. I can either try the track rea...

What's even more puzzling is that somtimes the C2 bytes crush other bytes, and sometimes they are inserted between two bytes (I could see that by saving the reading buffer and comparing several readings of the same track) Did you try to read a track on the other side or elsewhere on the disk (at the...

Maybe not that much.
I can't recall exactly, I think he at least tried to, but the article I was thinking about actually uses the parallel interface. CEO mag issue 122, pages 13-15 (June 2000)

Thanks to all for the replies. I am a bit confused... You say that nibble does not have this problem, but in your tests it does include the spurious bytes? Hehe, it didn't seem to happen ;) Because at 1st I didn't notice it visually, except very few mistakes here and there (and at 1st I thought the ...

Fabrice did, you'll find articles in the CEO-Mag, but I can't recall when... I'd say between 1997 and 2004, if that helps

I must confess I don't really know (as I don't really know what polling registers means ;) ) I (as well as Nibble it seems) don't handle anything, just set a few parameters and call the reading routine. The reading routine (quite big) is described in Sedoric à Nu from page 179 to page 186. Unless I ...

This is driving me crazy :x . I'm trying to get a reliable way to read a track, to make a universal disk transfer tool. So thanks to Fabrice, I'm using the Sedoric routines (at $CFCD in Sedoric kernel - see Sedoric à Nu page 179 for details). This is done by setting some parameters (drive, track, da...

One year later
To simulate CRTL + Key, just put $40 + ASCII code of the key into memory $02DF.

For instance, L is $4C; so put $8C into $02DF and the screen will be blanked as with CTRL L.

Dbug wrote:

Symoon wrote:(1 pass the the 2 first bytes, and two passes for the remaining six)

Bytes... or bits?

Ooops, bits, you're right
I made the mistake in my 1st post too, I'm a bit tired I'm afraid :-/

Given the current penchant for alternating colours on every line, would it be worth scanning every column twice. Sure the alternate colors wouldn't help, but they mainly "only" occur in a single column (the 1st, defining the global lines color). Actually it would be interesting to test an...

What would be an interesting test, is to see if we would get better compression ratios by using FilePack per column instead of per line :) Well I found the idea interesting because of the HIRES screen structure: 2 dimensions, the vertical one being more important than the horizontal one. 200 bytes ...