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...
Latest articles
sync’ing to the 0x4489 0x4489
Well, this wasn’t as easy as I first imagined. There are some issues: 1> By the time you’ve detected the 4489 4489, it’s too late to do much about it. This is because I’m writing one bit at a...
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.
CLICK ON THE IMAGE TO DISPLAY A FULL RES VERSION.
adding more commands
Now that I *think* I’ve got a handle on the reading portion, I’ve been adding a couple more commands. I added support so that the SX knows what cylinder number it is on. The F and B commands increase and...
Found one issue
Well, within an hour or so of getting my new LogicPort logic analyzer hooked up, I’m at least noticing some symptoms that I haven’t seen before. The drive is putting out(or the logic analyzer and my sx is...
pullups
These are all 2us per division on the scope. Top trace is the actual MFM, bottom trace is the entering and exiting of my ISR. You should see an entry into the ISR for every falling edge, and every ~2us afterwards. 1k...
