SuperHouse #35: Sonoff BasicZBR3: Zigbee, not WiFi!

hi i'm jonathan Aqsa and this is super house right from the start of the sawn off line from the very first model they've always used the expressive esp8266 or 808 5 processor that's because they use Wi-Fi for the communication but I too have just brought out this new model it's a sonic basic Zed br3 it drops Wi-Fi it doesn't use the expressive chip anymore it is as a Texas Instruments chip instead and it uses a ZigBee so what's that all about now in some ways Wi-Fi and zeebee are similar they both use the 2.4 gigahertz unlicensed spectrum so they do have a lot of similarities they're both designed to provide data communication between devices but they're not really competing standards they're complementary they have different design objectives Wi-Fi is really designed for high throughput it's used for situations where you might want to stream video or normal internet access ZigBee is much lower throughput but it's also much lower power requirement if you have a laptop with a big battery or a mobile phone Wi-Fi is fine but if you have a device that needs to be on a wireless network and run few years on a battery the Wi-Fi just isn't going to cut it and ZigBee is really designed to meet that need it's much lower throughput typically 250 kilobits a second so like a thousand times slower than your typical Wi-Fi network but it does have some other advantages lower power but also support for a networking strategy called mesh networking Wi-Fi uses the star topology you're putting access points and make sure that they cover the entire area where you want devices to have access the access points themselves use some kind of a backhaul like cable Ethernet to link between them and then your devices each connect to the nearest access point or the one with the best signal degree supports a topology called mesh networking with mesh networking you start with a coordinator and then devices can connect to that coordinator wirelessly just like they would with a Wi-Fi network but the difference is that unlike access points you don't need to put coordinators the entire area that's because the devices are capable of talking to each other as well they can pass messages directly between each other they don't have to go through it the coordinator if you look at this example you'll see that some of these nodes have multiple devices connecting to them these need to be powered on constantly because they need to be ready to receive messages and pass them on these devices are called ZB routers now as if your router isn't really anything special it's just a ZB node it's just that it happens to be one that is connected to multiple devices and is ready to pass on messages these other nodes that are only ever connecting to one thing as igby n devices now ZB n devices can make use of a deep sleep strategy to really go into very low-power state they might use only a few micro amps which means you can have a device on a coin cell they can run for several years so a typical ZB network consists of these three device types the zbn device which is the lowest power and that can sleep between activity and it only ever connects to one other device ZigBee routers which is just like as ubn devices except that they require constant power because they have to be ready to pass messages at any time and the ZigBee coordinator there is only ever one of these on the network you can think of it as being like a DHCP server on a normal network it sets out addresses and keeps everything working together so it requires constant power and it manages the security for the network so what does this mean to you well if you have ZigBee devices in your house having some Sun off zeebee could be really useful that's because they require constant power they need it to drive whatever load is connected to them and that means they can act as a ZB router if you've got some sign of Z B's around the place your n devices like temperature sensors that might run off a coin cell have a router they can connect to and it'll help your overall network be a bit more resilient now I have approximately 0 ZB devices right now I'm going to set this up as if I'm starting totally from scratch I've got an Amazon echo plus which is the new echo version that has ZB built-in disconnect as a coordinator I've got a Philips hue globe and we've got the this on/off ZB I've plugged in the echo plus and turned it on I've also bound it to my Amazon accounts that's ready to go apart from that it's totally factory and I put the hue bulb in here so I just turn it on it starts up normally and as far as I know it should now be in binding mode so I should be able to say I like the discover devices starting discovery this will take a few moments power on your new devices now and if needed put them in pairing mode should already be in pairing mode looks like it's discovered it I found first light and you can control it by save turn off first night hope they had to sit and wait for a moment because it had to wait for timeouts in case there were devices that were slow for now we should be able to say like the turn off first light ok turn on first light ok well that was pretty easy I haven't had to touch it all the setup was totally voice control apart from plugging in the globe and turning it on just tell it to discover devices it finds it and it's done so let's hook up that it's on/off ZigBee and see if that works just as easily but before i hook anything up I'm gonna pull this thing apart let's have a look at what we get in the box you know case should just clip apart same way as other song offs do let's see what we can find inside it's very fancy multi-piece she'll cover over a cover and there is a somewhat familiar looking sawn off from the bottom that looks a bit like a normal song off you can see the the input in the output side and we've got neutral pass-through and we've got active controlled by the relay but apart from that this electronics is all different it looks like the power supply is pretty much the same as what they have on over sign-offs but the interesting part is right here and for that winning a microscope there are a few things that are immediately interesting about this board firstly we can see the process are right here now if I get the lighting at the right angle we can see it to see see 25 30 that's a Texas Instruments chip which is based on the ancient 805 one architecture came out in about 1980 I think so this brand new device is running a nearly 40-year old processor well some things just keep hanging around now if we spin it around so that it's kind of upright the way you would normally look at the sign-off we can see some connections so pin one of the processor is down here it's rotated 90 degrees we can see a header along here which looks like a programming header and you can also see just up here there are a couple of connections that come up through here and this is a tuned circuit for the antenna we can see it comes up through here and then there is a PCB strip antenna meanders along there you can also see there's a whole row of vias now the top of this PCB is a ground plane and these vias essentially stitch the two sides of the PCB together the ground plane forms a horizontal RF barrier and these vias form a vertical RF barrier that go down through the board and that helps to isolate the circuit here from whatever is going on here and provide a good ground plane for the antenna to reference so we can see a couple of test points to p3 is up here and says it's ground so that's very handy it it's obviously connected through to the polygon here there is TP - we've got a button which turns this on off on and off and we've also got connectors that go through to the bottom board because this is a little sub board that sits on top we've got four pins here and then another four pins there you know if we flip this over just for a second you can see that we've got 3.3 volts here connected to this track so these two pins here are bringing 3.3 volts up from the bottom board to power this processor board and you can see that these two pins are connected to the ground plane so these four connections are all just the low-voltage power from the main board bringing it up to this processor board now looking over here we've got another four connections and they come through down here onto the bottom board now I'll just fix this focus a little bit because this is going to be interesting what we can see if we trace from this pin the track me end it along here and it comes to this transistor and that is connected to the relay just on the other side of the board that's the relay right there so whatever pin this goes to on the processor that's the one that controls the output we can also see a couple of tracks here that meander along and they come to this knot place to put print so they're not very useful that's I think for RF there are obviously some optional features they haven't populated on this board so the one we care about is this one right here whatever is connected to that pin that is the one that controls the output so I'm going to grab my other multimeter probe but continuity test it up here I'll put that on there and I'll just run it along to CPU see if we can get a buzz or there's one where is it just down here somewhere there yeah that one the second pin in now remember this is rotated 90 degrees now that pin on a cc twenty five thirty is got the datasheet here it's p0 underscore seven so p0 seven is the digital i/o on this that is driving the relay and just up here we've got the switch now if we use the handy-dandy ground reference which we've got here we can see that this side of a switch is connected to ground and now we can do the same trick I'll put a probe on here on the other side of the switch give it a bit of a run around I found something already where is it there that one so this one I could have visually traced it comes up to the switch and according to the data sheet that is p1 underscore 3 so if you're playing along at home and you want to hack around on this these peanuts are going to be very useful ok now let's look at this header now we can identify visually very easily a couple of interesting things this one's obviously ground you can see that it's connected to the polygon and if I touch this test point over here err I've got continuity and we've got we know we've got 3.3 volts on here so let's start from there and we'll check whether any of these other pins are 3.3 volts no one is so now we've got on this header with about 3.3 volts and we've got ground you know where else do these things go what we can do is do the same trick I just put the probe on there drag it around the processor see if we get a buzz nothing on there nope Oh got it that one right there so that pin which according to the datasheet is reset all right so we've got reset ground and 3.3 volts these are the only two pins we still need to identify do the same trick again connect onto here drag it across nothing drag it around I get a buzz nope what have I missed I must have not made a good connection as I was searching around here oh here we go that one right there so forth one across from the end and that means that this pin right here that I'm touching with the probe is p2 underscore one now that's interesting because p2 one on SEC 2530 is DD that's debug data so this is obviously a debug port and that means this one is one most certainly debug clock so I'll do a continuity test on that one let's see what we can find there we go it's the force pin across that means it is p2 2 which is debug clock so now we have the pin out for this so this is a debug header that's what you would use for messing around with the source code that's on that processor so just with a couple of minutes of poking around looking at things and deducing you know just using the data sheet and a multimeter and a microscope that's really all you need a bit of common sense so you figured out all the connections on here we figured out how it's driving the relay we found the pin out for the debug connector and we found the antenna and how that little tuned circuit is set up that gives us a lot of information about how this works so if you are wanting to hack around and make your own firmware to run on this and you knew how to do development on an eight-oh 51 core which is a pretty horrible thing to do I don't want to do it all the connections are there you could write your own firm way to run on this but one thing that is never ever gonna run on this is tez motor it's just not going to happen totally different processor architecture and there'd be no point anyway tez motor is designed for managing Wi-Fi devices this runs igby doesn't have any Wi-Fi Hardware on it so for now we're gonna stick with a stock firmware now if you do pull this on off said br3 apart and you want to put it back together it's one little thing to be careful of you look just on here you'll see that there are some pea sticking up and on this side there isn't on the PCB there a guide holds in three of those locations and not in the fourth so if you try to put this in the wrong way the board just won't sit down properly and you'll not be able to get the case closed so make sure you orient it so that the missing pin is in the top right corner and then it sits down perfectly don't we can put the cover on just make sure the button comes through that hole drop this on and input on the left and it's all good to go time to connect it up test it I've connected up my standard little sign-off test rig here I've got two globe running through past ground around it I've got to power this up and hopefully this is all going to go as smoothly as the as the huge globe did so I've just powered it up it's flashing which means it's in binding mode let's do the usual thing I like the discover devices well that's a good sign I did the same thing as the Hugh globe did when it was discovered I [Music] think it's gone just as smoothly is the first one so ten on first plug I like that ten on first light turn off there plug once again totally hands-free setup all I did was power it up do the auto-discovery and we're sorted this is looking pretty good so far now to really test the ability of the basic setup they are three to act as a ZigBee router what I've done is set it up just near the back door it's a bit hard to see over here the light is set up there and over near the front door of my house so right up here I've got the Philips hue lamp this is through about seven walls it's basically as far as you can get from where I am right here with the so there is no way that has coverage from this end of the house in order for messages to get from here to the hue at the front of the house it's going to have to be relayed through the Sun off here so we can now say turn on the first plug and it's turned on just here and if we go back to look at the front like that turn on the first light and that's turned on so we're definitely getting coverage through the the basic Zed br3 extending the range all the way to the front of the house so the basic Zed br3 seems to be pretty good as far as DB devices are concerned but nothing we've done so far is really that interesting from a real DIY point of view we've plugged the devices in and they just worked we don't have any modifications there's no custom firmware and even worse than that it's relying on amazon's cloud infrastructure to work and that's a big no-no for me so if my internet connection goes down these will stop working because I can't control them through but there are ways around that in a future episode I'm going to show you how to set up a gateway so that your ZB network can connect to your local MQTT broker and then you can get data from sensors and you can send commands without any reliance on cloud services at all so in the meantime go and build something cool [Music]

Channel: SuperHouseTV

Views: 60,282

Rating: 4.9488816 out of 5

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Id: yFwJAQFndEo

Length: 19min 3sec (1143 seconds)

Published: Tue Nov 05 2019