techtravels.org

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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SX software progress

Welp, since I fine tuned the PC to very reasonable numbers, I figure a small overhaul of the SX code is in order too. I had somewhat of an epiphany working the on the SX, which I haven’t *really* looked at in...

MFMSanityCheck

While I’m hesitant to post this at all, this is a quick and dirty application I threw together, and I do mean threw, that will check for valid MFM bytes. See the previous post for the link to the actual bytes. It...

even first or odd?

Despite having a couple different official sources, both AFR.c and floppy.c from the fellow amiga emulator says that the even bits come before the odd bits. This is true in the sector header decoding as well as in the...

new book

I recently received “On the Edge: the Spectacular Rise and Fall of Commodore” and have read about half of the book so far.  Very interesting read.  It’s fun to read about how the various Commodores...

Commands A and B implemented and working

Ok.  I got two commands A and B implemented and working. Command B from the PC instructs the SX to enable interrupts, and get ready to receive a track into fram.  This command will eventually be expanded to actually...

still giving me trouble

I spent some time on the project last night.  Still no-go. The SX and the software is behaving as expected by responding to commands, transferring the buffer, so and so forth.  I’m getting garbage data from the...

java client works

Well I’m producing correct .ADF’s with the new java client. The terminal mode is also finished and working. I have some various odds and ends to wrap up with it, namely allowing the user to save his...

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...

a little code review today

While my send UART code has been pretty solid for some time, I’ve always though my receive uart code needed doublechecked and worked on. I spent some time today just going through the code, graphing out some...

PC xfer working now, timing in order

Welp I pretty much solved the big problems I encountered over the past couple weeks. Ground issues — turned out I was attaching ground of one interface to Vdd on another interface. That was solved by actually...