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...

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java client preview

I’ve put up a preview of the java client in action. It’s a 2 minute video with narration. You’ll need a DivX codec installed in order to view it. I probably could have messed with compressing this...

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...

more followup winIO vs inpoup32

I did a little informal write test. A small tight loop that simply raises pin 1 and then lowers it again. Both in as little code as possible, as clean as possible. WINIO: Total time to raise and lower again, 2.5us...

going around the problem

Welp, I’ve ordered a new, but cheap ($5.99!) regular PC floppy drive from newegg.com.  I like this end result much better anyways.  PC drives are much more available, popular, cheap, and so on. was worried about...

Parallel port access in win 2k

Accessing the parallel port directly under Windows 2000, XP, etc in a standard user app is not natively available, but there are a couple different solutions available. The free one I use is called WinIo, and it is...

Good news. Floppy now under SX control

OK, so I finally bit the bullet and have the floppy drive under direct SX control. I have my amiga power supply, which is a modified PC supply with harddrive leads powering the drive directly with +12v and +5v.  I also...

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...

new book

I picked up a copy of Reversing: Secrets of Reverse Engineering this past weekend. I have about 5 or 6 chapters read. All very good. It was published April 2005 or thereabouts, and so its much more updated than the book...

PC to SX transfer images

I haven’t spent much time within the last few days on the project. Looking at the data on the PC, I think that there are still some problems. I think the problems lie in the fact that the interface to the parallel...

Success!@#

I hestitate to jump to conclusions, but I think I just passed a crucial first step in getting this to work!@#!# After adjusting some timing on my new code on the SX, I’ve found my first 0x4489 0x4489 pattern. This...