techtravels.org

inital results on error correction

While I have yet to actually implement the full-scale error correction as I want to, I did some manual tests today. I basically took a track that I was erroring out on, and swapped in 1-bit away values for the bad bytes.  In some cases, it appeared...

Latest articles

Timeline

I’ve put together a time line of events starting from November 2004, the initial idea.

CLICK THE ABOVE IMAGE FOR A FULL SIZE VERSION.

revisited memory routines

I was looking over my reading and writing routines. Minimums for the fram are Clock high min. 28ns Clock low min. 28ns Data setup min 5ns I write in two places: First, when bits are coming in from the drive, and the ISR...

Of timing, and general progress

I’ve determined that programming is like whack-a-mole(only took me 15 years to figure this out!) Fix one problem, and another one that already works stops working. This is what happened to me yesterday. My ISR...

first real world tests

Well I tried to read about 70 disks in via my project tonight. I had mixed results. First, the Teac loves HD media but doesn’t fare as well with LD media. The Samsung hates HD media, but does very well with LD...

updated code and comments

  Here’s a current version of the code.  I cleaned up my code tonight, added a bunch of comments, and tried to explain and document what I’m doing and the logic behind it. The current code is so much better...

new pictures

 

As you can see above, we have a “10” (4 us), another “10”(4 us) and a “1000”(8 us) chunks of data.  Little noisy there.

Latest attempt

Tim mentioned something in the last post regarding SYNC which really had me thinking about how to SYNC the data coming in the drive with the data going to the UART of the USB2SER converter. Then I was thinking, now that...

added version control and another command

I’ve really wanted version control for a long time.  The ability to go back and undo diverse changes across sessions is valuable.  I also feel a little safer and don’t mind doing semi-destructive edits...

even first or odd?

Despite having a couple different official sources, both AFR.c and floppy.c from the fellow amiga emulator says that the even bits come before the odd bits. This is true in the sector header decoding as well as in the...

new book

I recently received “On the Edge: the Spectacular Rise and Fall of Commodore” and have read about half of the book so far.  Very interesting read.  It’s fun to read about how the various Commodores...