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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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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...

Current status updated

Current status updated I was originally going to use a Microchip PIC, but they are just too darn slow. I gave up on the idea of using the PIC as a one-chip solution, and tried to use it as just a clock generator feeding...

Good news good news. First perfect .adf

Good news indeed! I’ve managed to create a fully functioning .ADF from a floppy.  I matched the output from my hardware/software combination with a “transdisk” output, and it matches exactly. I used...

minor success at 2:00am

well I’ve got MFM flowing from the PC drive now.  A couple of things: Pins 10 and 14, the pins I’ve been using since last night, appear to be correct. Pin 10 is the motor lead.  Dropping a corresponding SX...

Found another UART timing issue

Ok. A post or two back, I mentioned that I wanted to rework the receive UART because it wasn’t working perfect. I fixed that, and now it’s reliably receiving. I also mentioned that my sending uart code was...

mid-january status

So here’s where I’m at: I know my memory read and write routines are good.  I calculate a checksum as I’m writing the data, and on the output of that data to the PC, I also calculate the checksum. ...

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...

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...

interesting results

OK, I’ve applied the “double 1’s” fix that I talked about earlier today. This definitely helped things. I think my results are quite possibly the best I’ve seen them yet. Now, my SX...