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 software

I’ve been working on the Java software the last couple days. Trying to read from RXTX is producing only 3968 bytes per read.  It looks like my USB -> serial converter uses a “transfer size” of 4096...

man am I a slacker

Yeah, I’ve been slacking lately on the project. School has been keeping me busy, work too. My current problem is that something seems up with the data checksum routine, the code on the PC that is processing the...

Halloween 2007 AFP updates

DTR-based PC to SX flow control is now enabled and working, thanks to jd2xx. It has been tested, and SX responds appropriately to a STOP request. Strangely, with the new jd2xx code, it doesn’t appear that flow...

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...

new design on SX software

Welp, I’m having trouble tweaking my existing SX code. If I modify the timing of the current code, I’m getting all garbage output — even adjusting small amounts to one side or the other, produces much...

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...

funky idle routine

I’m making some progress. On a whim, I told my software to never go idle, to simply stream data constantly. I’ve never liked how I handle the idle state, and I currently lose whatever data thats in the shift...

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...

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...