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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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reworking my uart

Well I rewrote my recv and send uart, and with the help of my logic analyzer, I’ve tuned them up pretty good. I’m getting some transfer errors, somehow, and I think its related to buffer size. I read a disk...

great performance increases

Today I’ve worked on optimizing the performance of the AFP reader and have made great strides. My original track times were nearly 475ms. This was 300ms reading the actual disk, 125ms transferring, and process...

On speed optimization

The theoretical limit, assuming 300rpm drives, is 200ms per track. Or 400ms per cylinder, or 32 seconds per disk. Most attempts read slightly more than one track. I read 16,384 bytes, or 262ms worth. Right now, if I...

Parallax USR2SER

So I got my Parallax USR2SER in yesterday. Man is this thing tiny!! About the same width of my finger, and about 1/3 the length! And its mostly surface mount stuff….. It works like a charm. Easy installation, I...

Canada Post sucks

So I made the mistake of having an Amiga book shipped from Canada using Canada Post Expedited USA shipping.  It was dropped off at a post office on Nov. 17th in Mississauga, Ontario.  Now Mississauga is about 300 miles...

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...

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. ...

Creating more test disks

From both Tim’s suggestions and from a reinforcement from Agans’ Debugging book, Chapter 6, “Divide and Conquer”, they suggest to “Inject Easy-to-Spot Patterns”. And of course, I knew...

sync on data

The more and more I play with this I find that I’m limited with visibility. Its tough to debug when you constantly have to deal with this overhanging problem : The data arrives at my hardware, and to the PC...