KingEdwardII

Its all about minimising voltage drop for the feeds to the track - the bigger the wire size, the lower the resistance and the lower the voltage drop. 16/0.2 is roughly 0.5mm2, which is a bit on the small side, particularly if you have a long cable run (say 3 metres or longer). I use 2.5mm2 wire derived from mains flex for my power bus and 1.0mm2 wire for my accessory bus. Yours, Mike.

I know that this might sound stupid, but have you got the 21-pin decoders installed the right way round in the '66? It is possible to mount a 21-pin the opposite way and if so, it would not work. If they are the right way round, then my suspicion would fall on the wiring in the '66 - has a wire come adrift? Yours, Mike.

Have you tried the Firmware Recovery procedure described in 3.8 of the User Manual? Mike.

Well, I think you can "get away" with quite a lot more if you model a preserved railway. All kinds of locos hauling all kinds of stock. Formations that fit the available space. Mixtures of different eras. GWR King hauling a fine rake of LNER teak coaches? No problem - happens in the real world on the preserved lines... Mike.

& I have come across another DCC servo controller which seems exceptional value: https://chesterfield-models.co.uk/product/arduino-dcc-sniffer-relay-servo-decoder-all-in-one-copy/ ...controls 16 servos using DCC commands.

There is the Digikeijs DR4024 DCC servo controller: https://www.digikeijs.com/en/dr4024-4-channel-servodecoder-with-4-additional-switching-outputs.html ...controls 4 servos using DCC commands

That is definitely what I don't want to do. The reason is simply that the mobile devices I use are not dedicated to running only Engine Driver apps - so having internet access is important to them and so the house WiFi is the best connection for them. It is also necessary for the Pi 400 to have internet access for software installs & updates and it also needs access to the house LAN for file sharing, backups, etc. I could connect all the devices to the house 5GHz WiFi, but in practice, connecting the Pi 400 via Ethernet is straightforward and simple for me since the Pi 400 is static and there is an RJ45 wall port within a short distance. Mike.

I'm assuming that you've never programmed this decoder before. In which case it will have the default address value of 3. Have you tried using loco address 3? Mike.

I think that Meister Bach would have been astounded (and pleased) at that use of his music. Sheer artistry.

Nah, beans is orf...

Keith, Hmm - the software developer world definitely ain't like that! As far as the Pi folk are concerned, they would not see the Arduino as a competitor, but as complementary technology - I've seen plenty of projects with Pi + Arduino. The Pico takes the Pi ecosystem into a new space that definitely competes more with Arduino, but I can understand the thinking that makes Linux the focus of their work for developers. I switched to Mac from Windows over 10 years ago for software development reasons, but in reality the rise of cloud computing has enhanced the status of Linux immensely - it is the most commonly used platform for cloud computing apps and dominates the newer technologies of VMs and Containers. It is also increasingly common in IoT devices as they incorporate mainstream processors. Software developer tools are generally highly advanced on Linux - and it is also easy to run Linux on Windows and Mac systems using VMs. So, for the Pi ecosystem, doing development on the Pi version of Linux is like falling off a log. Yours, Mike.

Yes indeed - the big hills disappear off to the southwest below Ludlow and you then enter into the rolling countryside that makes up much of central Herefordshire - only as you head back towards Wales south of Hereford do the big hills reappear to the west. Great cycling country. Which the added attractions of locally made cider and perry make into a wonderland Mike.

Curious the way the kit treats this, since in the original, there is serious steelwork along the edges joining up the ends of the roof trusses and the valencing is really decoration on top of this. Yours, Mike.

I used to wander around under those canopies as an 8-year-old - my school was right next door to the station. Great fun watching the fly shunting in the goods yard from the end of Platform 5. In 1965, Aberystwyth still had a very substantial goods yard on the north side. For what was really a quite small town, the station was truly imposing. Your work on constructing the canopy looks great. Mike.

OK, so after doing a little bit of reading: - Notepad++ is simply a Windows text editor tool, that in this context is intended to be used for editing source code files and such like. - This is in preference to the default Unix/Linux Vim editor (which in my opinion is very much an acquired taste, like Marmite ) From what I have read, IF you want to select Notepad++ as the default text editor during Git install, THEN you have to have Notepad++ installed FIRST - and the Pico docs don't tell you this. Notepad++ can be downloaded and installed from here: https://notepad-plus-plus.org/downloads/ and the overall process of installing Notepad++ and then installing Git to use it is described here: https://www.theserverside.com/blog/Coffee-Talk-Java-News-Stories-and-Opinions/How-to-set-Notepad-as-the-default-Git-editor-for-commits-instead-of-Vim You will note that the dialog that lets you choose Notepad++ as editor also presents you with a list of other editors as options - if you prefer one of those and have it installed, by all means select it from that list. Of course, us Windows and Mac users are the poor relations here - there is a throw-away comment on p33 of that getting started document which says it all: "the main supported platform for developing for the RP2040 is the Raspberry Pi" and since the folks making the Pico also make the Pi, I can hardly blame them. You will note that all the preceeding chapters of the document, starting on page 5, are about installing and running the SDK on the Pi. They even supply a script to automate all the installation and configuration work on the Pi (also on page 5). So, when I turn my attention to the Pico sometime in the future, I suspect I shall do all the work on my Pi 400 system, which I acquired mainly to run JMRI and automate my layout. Now I can see that it is likely to have other uses as well. We need to remember that the Pi 4 & Pi 400 are really fully-blown computers that can be used for serious software development - a very different situation from the original Raspberry Pi. Yours, Mike

Welcome to the wonderful world of Software Developers Git is a software version control system which handles updates to software under development. It is probably the most commonly used tool for this capability amongst software developers. It is open source software. I'll try and provide you with assistance on this, but a problem that I have is that I don't have a Windows machine - I have Mac and Linux (Raspberry Pi) - so I may have trouble reproducing the situation that you have. Yours, Mike.

I'm a bit wary of diving in here, since this could turn into a very long conversation The main documentation page for the Pico is here: https://www.raspberrypi.org/documentation/pico/getting-started/ - the slightly alarming thing is that this stuff is still steaming in the morning air - the last update I saw is marked as Feb 1 2021... However, it is where you should start. In many ways, it is perhaps best to look at the SDKs since these really dictate what most folks will do with the Pico - they have C/C++ and Python SDKs available. Choose your poison... Now, the Pico claims to have a main processor with 2 cores ("Dual-core Arm Cortex M0+ processor") - BUT the Pico is a microcontroller and so it ALSO has 2 PIO blocks (PIO = Programmable IO), each of which has 4 state machines and these deal with I/O. (See Chapter 3 here: https://datasheets.raspberrypi.org/rp2040/rp2040-datasheet.pdf). So each core on the main processor can execute one program at one time - so 2 cores implies potentially 2 different programs at the same time. But since the Pico is all about controlling IO, it is those PIO state machines that are going to matter most - and they run specialized I/O programs. And yes, the 4 state machines in each PIO block can be executing different specialized programs in parallel at the same time. "Multi-threading" is a mechanism within a single program for running two or more things at the same time, which can be used to exploit processors with multiple cores (although multi-threading was invented as a general idea that can actually run perfectly well on a single processor/single core system). So, for example, you could have a program with one thread dedicated to handling the user interface (screen output, user input) and another thread dealing with I/O involving your train layout. Most modern programming languages have facilities for handling multi-threading in one form or another, but the asynchronous nature of such programs can be a challenge to get right... I hope that this helps... Yours, Mike.

So, is this a case of lies, damned lies and web pages....? . Thanks for picking up on this, John. I certainly was not vouching for any particular decoder in my posting - just indicating that there are such beasts in existence. I've not yet had the need to use one, thankfully, since the choice is somewhat limited - but when it comes to decoders, some locos have a painfully small amount of space available. I suppose it is this that has led to some modern designs placing the decoder in the tender. Yours, Mike.

Welcome to the wonderful and weird world of DCC. Job #1 when fitting a decoder to a loco: find space for it to sit... Is there space for it in the boiler barrel/smokebox area? If you could extend the wires for the decoder, can you fit it in there somewhere? I had to do this type of arrangement for my Hornby 72xx. Putting a decoder in the tender is a tricky business, with a need to a) enable the wires to be detached when required to remove the tender and b) disguise the cables so that they don't stand out. My Hornby King and my Heljan 47xx have tender decoders, but they came built that way, with black wires between loco and tender and a plug and socket arrangement to enable detaching the tender. Personally, I would only place the decoder in the tender as a last resort and I would seek out an appropriate plug and socket mechanism as a first step. One other thought is that there are some decoders which directly fit onto the 8-pin socket, essentially replacing the blanking plate - if you had one of those, would it fit? e.g. https://www.dccsupplies.com/cat-196/8-pin-direct-decoders.htm Yours, Mike.

They don't call it "Skull Attack" for no reason... ...but it is necessary at a Welsh breakfast to wash down the sand from the laverbread & cockles Mike.

I would really appreciate a model of the reconstructed Broadway station on the Gloucestershire Warwickshire Railway. Rebuilt from scratch, it is an excellent representation of what has been achieved on preserved railways, while also reflecting the GWR in the Edwardian period. From the GWSR Broadway Maintenance blog: What I like about this station is that it is relatively narrow (1 room deep) but extends a long way along the platform. Yours, Mike.

Well, there are other Motor & Servo control HATs available for the Pi, including ones explicitly designed for the Pi Zero. e.g. https://thepihut.com/collections/raspberry-pi-motor-servo-hats/products/motozero A bit more expensive than the previous linked one, but it does handle up to 4 motors. Yours, Mike.

I really like the "powered Caboose" concept linked above. It allows the slip coach to be treated as a regular coach most of the time and then switched to powered mode for the slip operation. Very neat. Regarding the mechanism for detaching the slip coach - if you're going to have a loco decoder installed in the slip coach, then you could use the Precimodels approach to uncoupling, linking the uncoupling unit to a function on the decoder: https://www.precimodels.com/en/ Yours, Mike.

For us software guys, a package that is 5 years old is worthy of archaeology rather than use... Yes, as others have recommended, I suggest that the first thing to do is to upgrade to the latest JMRI - 4.20. Yours, Mike. PS I note that Zimo has provided several updates to the decoder software since 2016 and that V40.1 is the latest for the MX645 - you might like to check which version is currently loaded on your decoder - see http://zimo.at/web2010/support/MX-Decoder-SW-Update.htm

Seek out MTB MP1s: https://www.dcctrainautomation.co.uk/mtb-mp1-point-motor-6-pack.html Small, neat and the clever design means they lock at the end of travel. Certainly fit in less than 50mm under the board. They can be operated with DC, but I have 30+ driven via DCC using Digikeijs DR4018 units - and now displayed and controlled on a touch screen via JMRI software running on a Raspberry Pi. Yours, Mike. PS They have a built-in switch which can be used to handle frog polarity etc.