Telldus has a set of nice little gadgets (“Tellstick”, for short) that both allow you to control remote switches over radio (433.92 MHz), and to read sensors transmitting on that same frequency. Telldus also has a backend service, Telldus Live, which offer Tellstick users scheduling features (turning lamps on/off at certain times, or when certain conditions occur), as well as showing the latest sensor readings.
The above is at least true if you have a Tellstick Net, which connects to your home network and sends device and sensor data to the Telldus Live service. You can also achieve the same thing with the non-connected Tellstick models, and an always-on computer running Telldus’ software.
Anyway – let’s assume that Telldus Live can see your switches, sensors and other connected devices. Would it not be cool if you could bring all that data into Node-RED, and from there create whatever feature you dreamt of.
How about sending an SMS when the garage door is still open, but your presence data indicate that you have left for work? Easy.
Or the opposite: Send a tweet to your Node-RED server, which will then fire off an event to Telldus Live, turning a switch on, and by doing so closing the garage door? No problem.
Websockets are cool. They are the modern sibling of http in that they run over tcp, but websockets offer a lot more, most notably full duplex (i.e. data can be sent in both directions) and realtime delivery of messages.
Those two features enable the creation of web pages that update dynamically as soon as new data is available on the server. No need to reload the web page in the user’s browser.
I have been struggling with how to get websockets integrated with MQTT on my Synology DS1515+ NAS, but in the end it turned out to be pretty easy!
As noted in a previous post, a new Synology DS1515+ NAS landed here the other week. It’s a very nice products in most respects, but a couple of rather annoying details bring the overall impression down – more on that in a later post.
The DS1515+ ships with 2 GB of RAM, with an extra, empty memory slot available for memory upgrades. 2 GB is really on the low side if you intend to run additional applications on the NAS. CrashPlan for example is built on Java, which is pretty resource hungry to begin with, then the memory consumption goes up with the number of files backed up.
Synology specs tells us that a 4 GB SO-DIMM can be added, for a total of 6 GB. Stories from the Synology forum however indicate that it is quite possible to replace both the internal (some disassembly required, probably voiding warranty..) and user accessible RAM modules, for a total of 16 GB RAM.
With a bunch of different SO-DIMM modules in the drawers here, let’s test them to see which ones can be used with the DS1515+ and which ones cannot.
The trusty Netgear ReadyNAS 312 has served very well over the past couple of years, and is still doing ok. It has however started to run out of space, and even though the disks could be replaced by bigger ones, it was time to move to something larger.
As much as I have come to like the ReadyNAS products in general, and the support forums in particular, it would be interesting to try something else. The Synology products seems to have a loyal following, the UI seems nice, and said to have good build quality.
The new DS415+, DS1515+ and DS1518+ models came out recently each sporting a quad core Atom C2538 CPU, that was quite tempting… The 415+ has two Ethernet ports, while 1515+ and 1518+ both have FOUR 1 Gbit ports. Nice.
A quick check on the Synology forums indicate that they are very active and at least as extensive as the Netgear/ReadyNAS ones. That’s just at first glance though – time will tell if there is both volume and quality there.