You should read Part 1 and Part 2 of this series if you haven’t already. A problem with the HUB75 display reared it’s head almost as soon as I started playing about with MQTT: occasionally the screen would flicker, only slightly, but just enough to be noticed. At this stage I was driving the HUB75 pins with my own RP2040… Read more »
It’s been eight months since I last wrote in this blog. To my regular readers, should I happen to have any, I’m really sorry about that. The main reason for the large gap is I had a full time job and therefore had a massively reduced amount of free time. I say had because it’s no longer the case for… Read more »
The bring-up of the keyboard controller board was a protracted affair. The first problem was obtaining an RJ10 cable. When drawing up the schematics for the IO board and the keyboard controller board I had naively assumed that the RJ10 cable I had salvaged from an old telephone was wired straight through with pin 1 connected to pin 1 etc…. Read more »
We moved house a year ago. To feel more attached to our new home I thought it would be nice to make a replacement for the existing, and somewhat shabby, house number sign attached to the wall next to the front door. The basic design I had in my head was a wooden oval with brass numbers screwed to the… Read more »
Working on the MPCNC has been a bit of a background project. It’s hard to believe I started printing the parts for it about four months ago. Here is a little about the MPCNC for some context. The project is the brainchild of “Ryan” at v1engineering.com. It is a set of 3D printable part designs, given away freely, and other… Read more »
After pondering on it for a while I’ve concluded that my projects lack variety. I really enjoyed working on the case for MAXI09. The CAD work was interesting and taught me much, and was not just a means to the end of a case for MAXI09. So much so that I want to do more of it. And I want… Read more »
One critical issue arises when attaching mechanical switches, as found in computer keyboards, to digital electronics: switch bounce. When switches are opened and closed, the connection across the switch contacts does not cleanly transition from its previous state to its new state. Instead the switch contacts will (literally) bounce between the old state and new state before finally, after a… Read more »