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

my checksum algorithm

So I’m using an XOR checksum to detect errors in the transfer between the SX and the PC.  I always thought it was a reasonably strong checksum, even though it’s still an 8 bit checksum. I found a neat...

Am I reading MFM wrong?

I’m beginning to think that I don’t fully understand the signalling coming out of the drive. I understand the concepts behind MFM (I think), but the actual application to this project, I’m not so sure...

Flow control

I’ve gotten away thus far without any flow control. I just started noticing that my software was locking up occasionally when reading a disk. It was locking up in the “read” portion of the code because...

redesign of read routine

After skimming the patent I referenced in the earlier post, I’m starting to come to the realization that in order to have an effective floppy controller, I need to implement a decent PLL which can better track the...

March 21st Status

Well, here’s where I’m at: The external amiga floppy drive is now hooked directly to my SX microcontroller.  The code within the microcontroller waits for a command.  If it get’s a “B”...

Let the fun begin!@#!@#

 
Everything has arrived!  I think the first order of business is soldering this darn memory chip…. Not sure how hard this is going to be, but I’m going to give it a shot!@#

RXTX and Java

As I mentioned before, I’m using RXTX to do serial communication in Java since Sun has dropped support for serial communication under the Windows platform.  I want to revamp my read routines on the java side...