Building a wooden cabinet

This cabinet was designed for the living room to hold our modem/router and NAS on the lower shelf, covered by a door and with a drawer above. The back is open to allow cables to enter and for airflow, but apart from this slighly unsual feature it could be used as a general side cabinet or bedside table.

Setting up an STM32F4 as an SPI device with FreeRTOS and STM32MXCube

In this post I’ll go over my steps to get an STM32F4xx microcontroller running FreeRTOS as an SPI peripheral/device/slave using DMA so it can run in the background while the main task is running. There are a lot of examples online of setting up STM32 SPI controllers, but very few where it is used in slave mode, especially with DMA and integrating this with FreeRTOS. In particular, the main problem I found is that by default, all the interrupt handlers have the highest possible priority (priority 0), which means that you can’t call FreeRTOS API functions from inside them. This means, for example, that you can’t send a notification to wake a thread from the interrupt handler. The solution is to reduce the priority of the DMA interrupt handler to below the level the FreeRTOS handler is running, as described below.

More fences! And a new arrival.

We finished off the final section of the “long flat” paddock fence, which means we’ve now got a fully finished large paddock where we can keep the bull and breeding cows separate from the rest.

Gate installation details

This time we have a close-up of installing a gate. This one is halfway along one of the sides of the long-flat paddock from the last post. We’d already installed one of the posts which the gate is swung from before starting the video, so it picks up after that.

Installing some gates on the “long flat”

Today’s timelapse shows us installing a couple of gates at the entrance to the “long flat” paddock. The previous gate posts were all wooden and were destroyed in the fires. The new layout is identical to the old one - all the gates survived and are being re-used.

Stockyard cleanup – timelapse

The old upper stockyard near the house was all wood and was damaged in the fires. This is the stockyard which is used to move the cattle on to the truck for transport - you can see the metal ramp on the right of the image above. This needs to be repaired before any cattle can be sold, which should hopefully be happening soon, so there is a timeline to get it finished.

We’re farmers now?

The latest project is helping out on the farm, repairing and rebuilding after the fires at the start of the year. First job, building fences!

Wedding beer and super sour

So I recently just completed a series of brews for a wedding - the light sour - which ended up going down a blast. As a result of brewing the beer many many times, I now have the recipe pretty much perfect. The only problem with posting it for everyone to brew, is that all were fermented completely open, and the yeast has been going for so long now if probably isn’t the same. My best guess would be to start with the Amalgamation Brett blend, that I used for my first sour beer, and this should be pretty similar.

Bench Power Supply Build - Part II

This is the second post on my power supply build – also see part I and the Circuitmaker project page. The aim of this project is to design and build a linear bench power supply with adjustable current and voltage and up to 2.5A output from 0-30V.

Temperature Logger

I have finally finished my temperature monitor and logging module, originally designed to monitor beer temperature as it is fermenting (beer, fridge and ambient temperatures). It is an Arduino-based device which measures and displays temperatures from multiple attached temperature probes and logs them to an SD card. This is an old project from last year sometime which has been sitting 95% complete, just waiting on an enclosure and some finishing touches to the code.