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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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Performance of the Hope Badge Computer

I’ve just managed to get some key components working this year, and as a result, the machine is becoming more usable. I wanted to measure the performance of this Frankenstein machine. Ideally, I’d use...

Reverse engineering the LCD interface

So I was having trouble getting the LCD working initially, so I ended up probing a working HDMI to LCD converter board sold by adafruit. You see, this board was driving my LCD just fine, but my FPGA couldn’t do...

problem with high density disks

I’m running into an issue with HD, high density, floppies.  The output on the scope looks just fine, but I get a consistent bad checksum on all the tracks.  I’ve tried with and without covering the HD hole...

inpout32.dll vs WinIo

From a previous post, I mentioned WinIo as a nice way of accessing the parallel port from win2k. However, it was slow. The authors said, “I should be using MapPhystoLin() anyways”, whenever I asked about...

Anatomy of a flux transition

I wanted to put up an image that displays an actual flux transition pulse coming off an amiga floppy disk whose data was encoded in MFM.

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