Inside Paula’s Floppy Controller, Part I
A 52 page functional analysis of the floppy controller inside the Amiga's Paula chip.
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Exploring Amiga retro-computing and Electronics
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Dataflyer 500 BUSS PAL validation results
Background As some of you may know, I’ve been working for awhile reverse engineering a DataFlyer 500 SCSI HDD controller from the 1990s. While I’ve had a working GAL replacement for the PAL for some time, I always wanted to do a side-by-side validation where I pump the same inputs into both chips simultaneously and […]
Hands-Free Debugging: Reviewing Gisler Precision’s Probe Holders
Disclaimer: While I purchased these myself at full price, Gisler did pay for shipping. This is my own opinion. If you’ve ever tried to hold multiple scope probes steady during debugging, you know how frustrating it can get. I tested three models from Gisler Precision to see which ones are worth adding to the workspace […]
Building a replacement Amiga 500 power supply
Intro If you’re into retro computing, you probably know the Commodore Amiga 500—a beloved classic with surprisingly capable hardware for its time. But like many vintage systems, the original power supply is often a weak point after decades of use. Whether due to capacitor aging, unstable voltages, or just a general lack of confidence in […]
Validating my dataflyer BUSS PAL replacement GAL
As some of you that have been following my reverse engineering efforts over the last few years, one of the tasks I took on was reverse engineering the BUSS PAL TIBPAL16L8-25 present in on the Expansion Systems Dataflyer plus SCSI-ONLY card. My PAL reverse engineering tutorial series on this site documents some of the steps […]
Recapping a Samsung 204B monitor
In September 2006, I bought a Samsung 204B SyncMaster monitor for $320 plus tax. It was a 4:3 monitor, ideal for specific tasks like my Logic Analyzer Cart. In July 2024, the monitor stopped working and wouldn’t power on. The only sign of life was a very faint flashing on the blue power LED on […]
Amiga QB Extract recently updated
There was a HDD backup utility for the Commodore Amiga called Quarterback, part of a suite of tools called Quarterback Tools. This utility allowed you to backup existing files on your HDD, compress and/or encrypt them, and split them across multiple floppy disks. This backup tool stores a catalog, which contains a number of directory […]
Couple hi-res images of 16902A mainboard
I just recently added another HP/Agilent logic analyzer to my collection. This time it is the 16902A. I needed to remove the CPU tray to replace the IDE HDD with a SATA SSD. As a result, I figured I’d take couple images with my copy stand and share them. Hope you enjoy! Full resolution is […]
Agilent Logic Analyzer cable teardown photos
So for today ladies and gentlemen, I present a teardown of an HP/Agilent logic analyzer cable. I think this is part number 16715-61601. This cable is used to connect one of a series of 40-pin compatible modules (many of the 167xx series, but not all) from the 60-pin connector on the LA side, to the […]
Creating a timeline of events
It’s often useful when trying to understand, debug, or reverse engineer a system to put together a timeline of operation from beginning to end. The result is a series of events where something happens first, then something else, perhaps some more “middle steps”, and finally the last thing. This can yield definitions of overall phases, […]