The Apple II’s CPU clock has jitter or a glitch. This issue is not new—it has been present since its original design in 1977! Bald Engineer uses an oscilloscope to show how often the glitch occurs and how to correlate that jitter to its source—which is useful when you are not testing 40-year-old devices. The device under test (DUT) in this video is the Mega IIe project. It’s a fully compatible Apple IIe built around the Mega II chip.
KiCad 8 just dropped. Here’s an AddOhms video covering eight must-try features! The February 2024 release brings a whole host of new stuff to the Schematic editor. However, the PCB editor, CLI, and Simulation tools also received attention. (There are something like 900 closed issues for the 8.0.0 Milestone!) Which of these is your favorite?
Learning to use a new oscilloscope can be daunting. In this video, I show 5 measurements you can make using just an Arduino as your DUT. Learn how to offset voltage, setup measurements, enable infinite persistence, save reference waveforms, AND trigger (and decode) serial signals. For this video, Rohde & Schwarz was kind enough to send me an RTM3004. This video is a follow-up from an ealier blog post which featured 6 scope measurements you can make with an Arduino.
Check out the AddOhms Episode 28 Show Notes for links related to the episode.
As promised, the Arduino team shipped the MKR 4000 VIDOR by the end of July. The graphical editor is still missing in action, but you can check out the board now. I received mine. In this AddOhms Live Stream, I turned it on and checked it out.
This video is a “working” live stream. Generally, I try to set up some demos and run through some canned actions. Not this time. I used the board once, on another computer. You get to watch how I attack a new board…live! Warts and all.
Key things I check out:
- How do you program the FPGA? (what does that even mean for the VIDOR.)
- The VidorTestSketch (communicate between the SAMD21 and the Cyclone FPGA)
- LogoDraw (the VIDOR draws the Arduino logo over HDMI)
- The include files for each of the VIDOR libraries
I’m writing up my experience so far, along with what I’ve learned. Until then, click below to see the 1-hour live stream.
This AddOhms episode is part 3 of the “design your own Arduino” series. In this one I populate a bare PCB, reflow solder it, debug a few issues, and load the Uno bootloader. Originally, I designed 2 versions of the board. One version contained an error that I planned to fix in the episode. Well, turns out, the “correct” board had two issues which were more interesting.
Check out the #27 show notes for links to a bunch of stuff in the episode, including the design files.
