2020-01-26
A “little while ago” I bough a Samsung “smart” TV from Costco. It was neither the cheapest nor the most expensive model. I was juuuust right. At that point Samsung’s smart TV shenanigans were well known so I made sure to disable automatic updates and I declined the user agreement during the initial setup. One of the very first annoyances I noticed was this “TV Plus” that would start blaring anytime I turned on the Read more…
2020-01-25
It has been a while since the last update and a whole lot of progress has been made. On the software side everything seems to work. For realsies this time. The full software stack compiles and runs(!) on both Linux and FreeBSD. On Linux it compiles using GCC and Clang. On FreeBSD only Clang is used since that’s the default compiler. To be fair I’ve only tested the client side stuff on FreeBSD, but as Read more…
2019-09-23
In the last post you said “The software is good shape.” I plug both boards into my workstation. Start the software. Error messages start spewing about bad checksums, buffer overflows etc. Narrow it down to a specific serial port. The serial port that’s built into the motherboard works just ducky. The port that’s an add-on card is causing problems. Start investigating. Eliminate cable, IO board, configuration, etc. Both ports work fine in text/human mode, but Read more…
2019-09-22
The hardware design is complete. All of the units that I will assemble have been assembled. The software is good shape. It hasn’t been touched in a few months, but last I worked on it it was in very good shape. The next step is actual physical assembly of the whole thing. Below are a few select pictures of the assembly progress. All taken with PotatoCam II. Where the magic happens, one of two. The Read more…
2019-09-16
Final assembly has begun. While waiting for the parts for the Beagle Bone expansion boards I started assembling the IO boards. I figures four at a time was a good idea. Find all the location on the first board and then copy that to the other boards. One component at a time of course. I was wrong. Five hours into this, my solder paste is getting dry, I’m getting anxious from sitting in one spot Read more…
2019-08-26
The VPSB (Vic’s Serial and Power Board) is functional. Fucking finally! The last function to be tested was the current monitoring of the attached peripherals and I am glad to report that it works. Not flawlessly, unfortunately. I will have to replace the 0.010 ohm resistor current sense resistor with something a bit bigger on “production” boards. Going to try a 1.5 ohm in its place. With two 3 ohm resistors in parallel current sensing Read more…
2019-08-19
How do I put this … the latest revision of the board works. The only thing that I haven’t delved into I2C, but everything that I have tried so far works. Completely. Which is actually extremely rewarding, since this has been a slog for a year plus. Some previous posts to catch you up: So much failure More failure Everyone on the fail train Well all of the problems have been addressed. Vic’s Power and Read more…
2019-08-04
Finally success. FINALLY. I finally have inrush current management under control. In case a refresher is needed, here are a few posts discussing the problem. https://www.simkus.com/2017-10-01/ https://www.simkus.com/2018-07-21/ https://www.simkus.com/2018-08-24/ To recap: Attempt #1 – relay. When the relay would turn on, the power supply would dip causing havoc. Attempt #2 – PWM drive of the low side. Electrical current is like love – it finds a way. By disconnecting the low side (negative rail), the positive Read more…
2019-07-30
I have been playing with the latest revision of the VPSB (Vic’s Power and Serial Board). I was hoping that this would be the last revision, unfortunately the fact that I crewed up the power supply footprint will prevent that from happening. I got the pin order backwards. This is the worst kind of failure since I can’t blame anyone else. Anyways, here’s the potato-cam picture: You can see the power supplies in the Read more…
2019-07-13
I had a touch of panic when I received a text from DHL that my PCB order from Elecrow would be delivered Tuesday, July 16th. Tuesday July 16th, you see, is when I’m scheduled to be flooded. The following is the river gauge closest to where I live. Tuesday July 16th is when we’re scheduled for a flood event thanks to tropical storm Barry. The even more disconcerting prediction is for the Comite river. They’re Read more…