JMRI and MQTT with Arduino part 3 of 3 - Supporting shift registers

[@ebjamville]

Chris if you want to save some bits you can define signal heads as if they were on a SE8C in JMRI thus representing four aspects with 2 bits: turnout address. Tried it with CMRI, likely works with MQTT. You have me sold me on MQTT for layout and home automation. Doesn't quite work with the shift registers - oops. I'm using ws2812 LEDs for search light signals. Similar to SP RR.

[@WirenwoodModelRailway]

Hey Joe! I remember reading about those but was never short of bits or addresses really. I think it's useful for people who use DCC for turnouts as it saves on decoders. And yeah, MQTT! Perfect for what i need! Regards, Chris

[@ebjamville]

@@WirenwoodModelRailwayChris I don't use Digitrax I was curious if its definition worked and sure enough it does. As to descrete signal head LEDs: Adafruit HT16K33 Breakout will drive 128 on I2C.

[@WirenwoodModelRailway]

@@ebjamville thanks Joe. Dale mentioned something very similar i think, they do sound very convenient, especially if they do away with the need for resistors. Chris

[@yenraccarnivor]

Great Vids, i've now also migrated away from CMRI to use MQTT, as i already had the broker for home assistant ( which i plan to use to assist with some of the automations i have planned. I've gotten the turnouts and sensors all migrated fine, but the LED's i had on the PWM boards I cant work out how to utilise, i used to be able to on/off and set a brightness with CRMI. but you use shift registers which i currently have none of. Is there a "simple" mod to the code i can make to use leds on PWM?

[@WirenwoodModelRailway]

Hi, i should think so as shift registers just complicate things really, so without them should be a little straightforward. There's an email address on the channel info, feel free to contact me if you like, I'm sure we'll work something out if you can give me a little more detail! Regards, Chris

[@Nealos101]

Thanks for all of your contributions there. I'm in no position to start something like this but I'm hoping to in the near future, and it is really hard to resist just up and getting all the parts and having a little play. We shall see; I do have a make shift workbench I can tide my time over until I can construct a proper layout. Are you still having relative success with MQTT? From your latest video it seems like you are, but always good to check as I don't recall hearing any gripes about it haha.

[@WirenwoodModelRailway]

Thank you! Short answer is yes, definitely! I keep meaning to make a 'two year review' kind of a video (it would be two and a half years now!) and when I was thinking about that, it got me thinking about the best and worst decisions I've made so far, in terms of cost in time, money etc. DEFINITELY the worst decision was to go with RS485, in terms of time. I just couldn't get it running reliably. I had nothing against C/MRI, it was just that RS485 was its natural conduit, I guess. RS485 was constantly failing, the cheap Chinese components incredibly sensitive and destructive - if one went, it seemed it could take out lots of other components on the RS485 bus, the issues spread like a virus. MQTT on the other hand, over ethernet and Wifi, which I'm much more familiar, comfortable and experienced with, has just worked and never caused any issues. The only slight issue is JMRI occasionally having timeout issues (usually at startup) with MQTT but that's very specific to my setup, and something the devs are actively helping me with (there are a few threads on the JMRI user group board if you're interested enough to search them out!) I think a test setup on a workbench is a good idea too, especially as you're starting out. On a smaller, concentrated setup it's easier to weed out any issues you might encounter while you're getting used to it all. Regards, Chris

[@Nealos101]

@@WirenwoodModelRailway that is very good to hear! My first degree course was around IP networking and MQTT had that familiarity about it, especially in terms of MAC address, IP Addressing and the like. I think I will in fact go for it in that case. The Mrs and I are currently in the process of moving you see, well, waiting for the contract process to move along to moving day, so after then I will have space to build my layout but before then yes I'll see if I can get a test rig setup. Thanks a lot - glad to hear it is working out and the only issue you've had is being investigated; I do know from friends the devs for JMRI are helpful like that and it's something to look forward to if I ever get stuck myself. Cheers Chris!

[@sid21177]

I’m curious why you’re sticking with mqtt when you got cmri working over Ethernet ??

[@WirenwoodModelRailway]

Ha good question! I think MQTT has more potential, for me. It's more than 0s and 1s, it can carry messages, like reporter output, RFID tags etc. It was a close run thing though and I definitely think that CMRI is among the best options for anyone who wants to minimise the amount of code involved. Regards, Chris

[@anfieldroadlayoutintheloft5204]

good vid

[@joedoe6471]

Great video Chris! I sent you an email about bitwrite and stuff.

[@WirenwoodModelRailway]

Thanks Tom, I finally replied!