The block diagram above show the Ethernet module. Starting with a dual RS-X to the backbone and a SPI based W5500 for Ethernet connectivity. In addition we add a ESP-12 for Wifi, SPI Flash for storage and a RTC battery & oscillator as well as the mandatory SWD connector. I hope to have a 3D…
A Modular PLC system will have some size & cost, and as a home central should be small, easy to hide and low cost it might be wise to produce a specialized “All In One” solution. The diagram above illustrate the content with “backbone” replaced by a MCU. The C firmware will basically only be…
Using STM32F405RG on everything is an overkill, but I can always consider dropping down to STM32F105RB/C later. This M4 gives us a powerfully MCU on each module capable of truly distributed processing as we are promoting in Plain. Ethernet Module is what I have started on now. This will host a STM32F405RG, 2 RS-485’s for…
I am toying with using my 3D printer to (1) print a module box and (2) to print PCB holders as illustrated above. This was an early draft – the idea is that you push the module in and use a screwdriver to mount it – I need to look for low cost alternatives here…
My previous backbone board had to little space between connectors + no connection for PSU & communication – this one has 10mm between connectors which is more realistic – thought I still expect one Add-On board to use ca 20mm width. The total width “as is” is 100mm, so it is still very small. I…
This came as a surprise to me – it is only 1,5 years ago I started doing SMD electronics. My previous experience had only been hole through technology. But, as hole through have so many limitations I decided to jump in and give it a try – the first component I tried was a LQFP48…
The good thing about a blog is that it is excellent for notes – if I make my work-notes here they are called “documentation” 🙂 The following are programming notes for the PSU Control Board: PA10 – GPIO J1-4 Relay 1 – Connect extra 12V – 36V If Relay 2 is On. PA9 – GPIO…
This pic shows my analogue regulator. You can see the 2 transistors and a fan in the back and my DIY load array on top left. I am actually quite happy with this after I mounted it on a proper PSU source in. The only things left is to get the current regulator working, but…
I purchased this Lab PSU 0-30V /5A from ZHAOXIN a few years back, but I have not really been using it much. What I discovered as I started using it was very dissapointing. This Lab PSY from ZHAOXIN is far from cheap – it usually cost 80ich USD + 50ich P&P as well as ca…
These cost almost nothing, so I bought a few and plan to use them on my Lab PSU. They have separate PSU and measurement cables – so initially I connected the PSU to the same PSU as I use – the result was that Voltage increased as Ampere increased. Realising the mistake I connected a…