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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will put up sample files

I’m going to put up a sample file or two, but I wanted to get the smallest complete group of bytes that I can…. ie like one full sector, etc. So far, I’m just basically streaming bytes, via disk copy...

more SX to PC tests

Although I think I’ve long had this working good, I did some more tests just to verify. Latest numbers: Each cycle is about 15.8us, 2us per bit, 8 bits, this sounds fine. This does confirm, however, what I...

SX software progress

Welp, since I fine tuned the PC to very reasonable numbers, I figure a small overhaul of the SX code is in order too. I had somewhat of an epiphany working the on the SX, which I haven’t *really* looked at in...

cleaned up the project

So after banging my head for awhile, things still aren’t working as they had prior to my stepping away from it. What I did last night was to partially dissassemble everything, and rewire a decent portion of it. ...

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...

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...

Changes to the PC side

With more and more things pointing to the PC, I’ve decided to really reduce the amount of work the PC has to do in its receive loop. I looked at Marco’s because his was designed to run (albeit in dos/dos...

current read problems

It seems as though when I have a read problem, its normally minor, and is a single bit error. I notice that the errors have a tendency for 0s to be incorrectly interpreted as 1s. So I get AB instead of 2B, AB instead of...

writing merged USB comm code

Now that I have USB receive working in the main PC code, its time to merge the USB transmit(and receive for commands) into the main SX code. I have two pseudo-code versions written. 1> First version uses the ISR to...

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...