keith
I followed the instructions at but when I tried to expand the partition after the copy, it failed with the following error: Primary volume header corrupt, trying backup. Secondary volume header corrupt, giving up...
FPGA eval board
One of these arrived today. Very cool. I’ve only done minor things with it so far — but I’m learning. I’ve got FPGAs by Example for Verilog coming within a couple days. Looks like a good book...
Brian Instruments Brikon 723 Floppy Drive Analyzer
$20 on ebay got me one of these Brian Instruments Brikon 723 Floppy Drive Analyzer Ever since I’ve seen this device mentioned in the datasheet of many different floppy drives, I knew I wanted to get ahold of one. ...
redone transfer routine
So my transfer routine has been a little flaky lately. I’m not sure exactly why but I think it’s related to the number of processes I’m running. While it’s a P4 2.4, I think USB scheduling is...
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...
logic analyzer on Amiga 500 Paula chip
So I’ve attached my Intronix LA1034 to the Paula chip, the 16-bit wide data bus, and the DMA Request line. I triggered the logic analyzer on 0x4489, of course. Here’s the results: (click for a full size...
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...
sleep inversely proportional to the AFP and no more tokens
So I have figured one thing out. The more I work on the AFP, the less I sleep. At least that’s how it’s been over the last two nights. Two nights ago it was 3am, last night it was after 2am. Ideas come and...
new read routine implementation started
Last night, until 3am, I spent redoing my read routine to incorporate the method discussed in the comment of the last post. Basically, I use the time between the pulses as an indication of the data. I store 2-bit...
redesign of read routine
After skimming the patent I referenced in the earlier post, I’m starting to come to the realization that in order to have an effective floppy controller, I need to implement a decent PLL which can better track the...
how the amiga reads floppies
So I’ve forever wondered, at the hardware level, how the amiga reads floppy disks. I’ve gotten bits and pieces over the years, but I’ve never really understood the bulk of it. So there are four main...
logic analyzers
I’ve recently received a couple emails on additions to the logic analyzer page. Once I get some time to check them out, I’ll make the corrections. I’ve been super busy with life — switched jobs...
Interesting article and comments
Someone on sci.electronics.design mentioned the following article: This is a Floppy Disk Data Separator Design Guide for DP8473 which is a floppy disk controller like the infamous NEC 765 controller. It’s a...
first day back
You know, I always hate the “first day back” working on a project. Things always seem to get screwed up between the time I last worked on a project, and that day. Even if nothing has changed. Or so I say...
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...
error correction using hamming distances
I’ve been thinking for quite some time about error correction. About using the structure of the MFM to our advantage. I’ve come up with something although I haven’t implemented the idea yet. As you...
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...
further development on the AFP
I’m about to bring a new member of my family into this world. As a new proud parent, I’m completely unsure about what this means in terms of time, dedication, and so on. I’m sure I’ll have less...
