2020-03-30
I have been working on integrating the grossly over-designed and needlessly complicated thermostat into the house. It has been mounted in the data closet (see here) and connected to the home network. All critical sensors and some of the optional sensors have been been installed. Of the optional sensors the attic temperature and the AHU supply air temp sensors have been installed. More on that later. The system is not yet controlling the house AC 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…
2019-09-16
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…
2019-07-30
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…
2018-12-16
Looking back at the post history, and it appears that I am quite the Chatty Cathy this month. Lots of progress being made. First order of business: I screwed up the naming in a bunch of places. Instead of referring to the expansion board as VSPB (Vic’s Serial and Power Board) I referred to it as VPSB (Vic’s Power Serial Board). Well it’s easier to rename it than to change all of the references, so Read more…
2018-12-15
So on a BeagleBone Black running Linux, how can one tell if a device is enabled. Lets say we’re trying to get UART2 and UART4 to work. Those are both serial ports. How can one tell if the serial ports are enabled (or just a singular – serial port)? Well because we pretend to be familiar with Linux we do a ‘dmesg’ and look for a serial something of some sorts, yes? That sounds reasonable. Read more…
2018-12-13
The new VSPB (Vic’s Serial and Power Board – catchy, eh?) is working very well so far. That will be a different post. This is about configuring the BBB (BeagleBone Black) the Vic way. During the development of this project, a new version of Debian was released for the BBB. Since I want to be hip and with the times I decided to upgrade to the latest version. Debian Stretch IoT is my poison of Read more…
2018-09-03
I know I’ve said it before, but I will go ahead and say it again: the end is in sight. In the last few days I’ve addressed the last few remaining issues: 1. Persistent offset on analog input #8 (ICD4) Turned out to be an input voltage offset issue. See here for more details. 2. ADC input weirdness on analog inputs 4-8 (ICD inputs) The short version is that the op amp output is at Read more…