I should have mentioned this before, but the Amiga Forever CDs and DVDs are really pretty awesome. The original commodora-era videos, pre-installed games/environment, everything is done very nicely. I have the 2008...
Archive - June 2010
on floppy adpll, this time, my solution
This isn’t by any stretch finished, but it does do what I’ve expected it to do. It responds both to differences in phase (counter is set to 0), and differences in frequency (period is adjusted in the...
results from adding the PJL
So, as I mentioned in another post, I added Jim Thompson’s phase-jerked-loop to the project. Phil had good luck using it with his DiscFerret, but it really didn’t help me. My problem disks are still...
motor speed variation tests
I collected roughly 1,000 index pulses from the Sony MPF920-E with one common floppy inserted. The motor speed variation was very very small. I am impressed as to the accuracy. Across 967 index pulses, all were within...
on recent disk reading results
(this was posted to Classic Computer mailing list, please disregard if you’re on the list. I think this is an important topic) The last two nights I’ve been busy archiving some of my Amiga floppy collection...
New demo video for the FPGA version of the AFP!
New demo video for the FPGA version of the AFP!
Enjoy!
(45mb download warning)
FPGA implementation of AFP demo
New pictures for FPGA AFP
Here are some new photos for the FPGA version of the AFP.
Click for full size.
Enjoy!
more real world tests
So tonight, I put my new FPGA implementation of the amiga floppy project to good use. I read some more of my collection of amiga floppies. GREAT NEWS. It’s working like a champ. As a matter of fact, I selected...
found bug last night
With this new FPGA solution, certain tracks would result in what I call a “short read.” A short read is any received track that contains less than 28,125 delta T’s, aka pulse times. Given a certain...
re-examining XOR data checksum used on amiga floppies
So I was wondering exactly how effective the XOR checksum that Commodore used for the amiga sectors was. If I read a sector, and perform the checksum, and the checksum matches the stored checksum, then the data is the...