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

logic analyzers

I’ve recently received a couple emails on additions to the logic analyzer page. Once I get some time to check them out, I’ll make the corrections. I’ve been super busy with life — switched jobs...

finally got some work into the VSC

Ok, so I’ve finally got some work done on this tonight. I’ve decided to go to a 4-line buffer system because it’s a more round number than 3 — makes everything easier to deal with. I’ve...

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...

losing data

I’ve been thinking more and more about how exactly I’ve been losing data. It’s alot of data. The worst case I’ve seen is about 140 bytes. This is 1120 bits, or 2240us. This is a LONG time for my...

Current updates

Wow. I can’t believe its been 20 days since my last post. Man have I been slacking. School has started up again, and add a week I was away on business/pleasure and there you have it. Here’s where I’m...

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...

simplified ISR

It looks as if I spoke too soon. I’m still having reading problems.  The data used to be forced into an MFM mold, but all that’s done in some cases, is to further corrupt the corrupt data. I rewrote my ISR...

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...