The WORKBENCH part 2

(Jeff Uk) #189

I believe the SPI bus on SX1301 is probably system throughput limiter and is ~2Mb/s IIRC so plenty of headroom on your system with >5Mbps though updates/upgrades of s/w and new downloads obviously wont be fast! Not sure if you are also taking a hit on latency (RX1/2 window timing?) but probably not much worse than using BBand over cellualr as backhaul? Still I recall 1st broadband connection was a turquoise Alcatel USB ‘Manta Ray’ modem serving just 512kbps on DSL so its a 1st world problem! How spoilt we are… :slight_smile:

(Tony Smith) #190

Oh Wow!! I thought my 10Mbps was on the slow side and was looking at other SPI based Ethernet controllers. If your 5Mbps works fine with a RAK831/833 then I won’t bother going any faster. Developing a simple POE power supply combined with a Ethernet controller for a compact RaspiZero / RAK833 gateway.


later today I test a bit more… I measured this without the forwarder running :blush:


Jeff (and other TTN’ers) a suggestion… upload a profile picture (in the console) :sunglasses:


that way it’s easier to recognise people imediate on the forum

(Amedee) #193

FYI, this is what I have for a RPi Zero gateway (Running my Docker containers):


Load and CPU usage is pretty much OK, so going from 1GHz to 700MHz (A or B+) should be OK.

Memory is not too bad, we stay around 110/120MB for User+Cache, so it might be doable with an a A 1st generation.
Something to test…
(I have the whole line of ‘B’ models here, but no ‘A’)



For better photos toocool !

  • update… this one is working so I have a back up now :sunglasses:


and I just ordered a few more of these SD cards, in China, for half the price

  • one week laturrrrrrrrrrrrrrrr … :wink:


that’s funny… the speed is 2 mb/s less on the packaging

(Jeff Uk) #195

Have you seen the price of a new camera/PC? Wouldnt dare capture this mug-shot! :wink:

Besides a little (semi)anon helps - will find a good symbol instead…looks like a rastaman with dreads & red/yellow/green Hat bands already taken :slight_smile:

(Tony Smith) #196

I have always used this brand and model and never had a problem. Even pull the power to turn off, no clean shutdown and still not had a problem.

(Gry Kyo) #197

I understand this is chancing to fate and not how it is supposed to work, but yesterday I was replying to a deep-sleeping node within the same RX window as an “interrupt-wake-TX” event. Hope that makes sense?

I had an instance of Node-RED use a TTN RX event to then trigger code in a Node-RED function to check a global variable and decide to reply with a packet or not. In the event of a reply being prepared it was being scheduled and transmitted during the standard RX window from the original interrupt/wake.

I understand this is the result of super low latency on the whole round trip but does show how fast the TTN back end and Node-RED/MQTT is in real life!

I should put up a little video…


yes that would be nice… or a little LAB story how exactly you did this :+1:

(Gry Kyo) #199

I do indeed plan to. Interesting little project for home engineer hackers :blush:

Raspberry Pi physically embedded in my home alarm control panel with digital GPIO inputs to ascertain if the alarm is armed or alarming. One other GPIO to drive the “Fire Alarm” input to my home alarm. Interfacing is done with 2N2222 transistors and a few resistors, very simple.

  • TTN node device will monitor the door of my shed.
  • It will wake and indicate any change in state.
  • Node-RED on the Raspberry Pi will decide if the alarm is armed
  • Node-RED on the Raspberry Pi will trip the house alarm if appropriate
  • TTN node device will drive a solar/battery piezo siren in the shed
  • TTN node device will beacon the Pi to know when the event is over

System already works (for 5 years or more) with WiFi & MQTT but power use on the solar/battery close to a tree is misery to manage!


PiZero gateway works with that slow dongle… no probs sofar :sunglasses:


(Remko) #201

RSSI of -48 dBi? Seems a mistake to me when RSSI is in dB-isotrope. It highly unlikely that you reference RSSI to an isotrope. “dBm” is more apropertiate IMHO


it’s the value forwarded to the backend… if its wrong kick @Charles :rofl:



(Remko) #204

Kick @Charles:wink:



saturdaymorning shopping… ’ that could be useful… some day :roll_eyes:

* update :sold out




Nylon Plastic Stick On PCB Spacer Standoff Locking Snap-In Posts Fixed Clips Adhesive 3mm Hole Support :woozy_face:

20pcs 20*20MM White Zip Tie Cable Wire Removable Self Adhesive Wall Holder Mount Clip/Clamp :woozy_face:

30x Electrical Cable Connectors Quick Splice Lock Wire Terminals Self Locking :woozy_face:

10pcs Quick Connect Terminal Electric Cable Wire Connector PCT-212/213/214/215 :woozy_face:



uhhhhhhhhh… ok got it :sweat:


it’s alive !


(Amedee) #208

Testing TPL5510…


Kicked, updated the repo, thanks for mentioning that