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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 QB Extract recently updated

There was a HDD backup utility for the Commodore Amiga called Quarterback, part of a suite of tools called Quarterback Tools. This utility allowed you to backup existing files on your HDD, compress and/or encrypt them...

motor speed variation tests

I collected roughly 1,000 index pulses from the Sony MPF920-E with one common floppy inserted. The motor speed variation was very very small.  I am impressed as to the accuracy. Across 967 index pulses, all were within...

sanding a 556 timer IC to expose the die

So tonight, just for the fun of it, I decided to sand, by hand, a 556 timer IC. I just bought an extremely inexpensive microscope and was very interested to see what pictures I could get from it. Unfortunately, for me...

working cause of bit errors

I think I’ve stumbled on something. I don’t think I’m capturing enough data. 13,824 has been my magic number forever.  It was larger than the 13,800 that Marco used in afr.c.  But I’m beginning...

Using a 74HC132E to square up the wave

A nice gentleman from sci.electronics.* newgroup suggested I use a 74HC132 on his web page here.[local copy] Below is the result of using this design, it worked perfectly. Only required one IC, one resistor, and one...

Getting closer….

So a few versions later, trying some different failed attempts, I am finally starting to get a little closer.  Here’s the best video I’ve got so far, but my image is still scrolling. If I can fix the...

first .adf written

Well, I’ve written my first .adf tonight! I threw together a quick routine on the PC side to query the SX for both sides and all the tracks. It generated a 901,120 byte .ADF file of a disk I had called...