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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...

Latest articles

on memory controller optimization

So I’ve been trying to optimize a freeware memory controller for my particular memory chip. I’m running into this situation where the DRAM to ALTRAM copy takes upwards of 24us per line. But I only have a...

quick memory check

So on bootup, I now have the hardware do a memory check.  I basically take and write out a bunch of values to the memory, and then read them back and make sure they read back properly.  The values written are based on...

more updates

I know I’ve been bad keeping you guys updated….. This doesn’t mean I haven’t been working on it, however. I recoded the ISR completely in assembly because I was just plain sick of the damn...

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...

changed from rxtx to jd2xx

Okey dokey. I’ve changed from rxtx to jd2xx.  rxtx didn’t support DTR/DSR flow control, which really is an absolute must for my application.  There would have to be hardware changes that I’d be...

recent status

Well, I’ve put a decent number of hours in on the project over the last couple weeks. I’ve mostly been “spinning my wheels” because I haven’t made much progress, but I think I’ve...