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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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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...

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...

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...

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...

FPGA eval board

One of these arrived today.  Very cool.  I’ve only done minor things with it so far — but I’m learning. I’ve got FPGAs by Example for Verilog coming within a couple days.  Looks like a good book...

error correction using hamming distances

I’ve been thinking for quite some time about error correction.  About using the structure of the MFM to our advantage.  I’ve come up with something although I haven’t implemented the idea yet. As you...

SX code

Ok so I’m using SX/B, which is BASIC for the SX. Even if you’ve never touched SX/B, it reads very easily, anyone who knows the PIC or other mcu should understand….. Here’s the logic behind the...

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...