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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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looking at the code this a.m.

Welp, I decided to take a look at my code today, although I can’t actually implement anything until after I get home from work. 🙂 Not sure if I mentioned this eariler, but I’m now padding the data sent from...

new isr thoughts

While this new ISR is indeed easier to understand and much more simple, I can’t help but remember what else my ISR used to do for me. The four things I really lose are: 1> Any type of double 1’s protection...

first day back

You know, I always hate the “first day back” working on a project.  Things always seem to get screwed up between the time I last worked on a project, and that day.  Even if nothing has changed. Or so I say...

On speed optimization

The theoretical limit, assuming 300rpm drives, is 200ms per track. Or 400ms per cylinder, or 32 seconds per disk. Most attempts read slightly more than one track. I read 16,384 bytes, or 262ms worth. Right now, if I...

Commands A and B implemented and working

Ok.  I got two commands A and B implemented and working. Command B from the PC instructs the SX to enable interrupts, and get ready to receive a track into fram.  This command will eventually be expanded to actually...

Schmitt Trigger

Welp, after talking with some smart guys on forums.parallax.com, it looks like the Schmitt Trigger feature on the SX is going to allow me to get rid of my 74HC132 that I’ve spent at least a couple hours messing...

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...

heat problems

As I alluded in an earlier post(s), my SX28 has been pretty warm. After doing a number of different tests, I’ve now ordered an infrared thermometer from amazon for $29.99. I want to find out exactly how hot this...

sync on data

The more and more I play with this I find that I’m limited with visibility. Its tough to debug when you constantly have to deal with this overhanging problem : The data arrives at my hardware, and to the PC...