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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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amiga floppy project activity

I don’t know how interesting this is, but I thought I’d throw it up anyways. I exported the posts and comments tables from the mysql database, imported into Excel, and then created an activity graph of the...

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...

memory chip mounted

Welp, I got impatient, and went to Radio Shack to buy their soldering station. I still have mine coming in the mail, but its ground from Arizona, which may as well be ground from Alaska. I soldered the header pins onto...

found bug last night

With this new FPGA solution, certain tracks would result in what I call a “short read.”  A short read is any received track that contains less than 28,125 delta T’s, aka pulse times.  Given a certain...

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...

Ground issues

Although I’ve been attempting to have a common ground for this whole project — I’m not sure that is going to happen. At least not at this stage of the game. I tried connecting the ground off the floppy...

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...