One thing that this article kind of glosses over is that there are a ton of different form factors for the ESP8266 (ESP-01 is the original, also the ESP-03, -07 and -12 are common).
Most of them are rather inconvenient to work with directly though, not least because they aren't breadboard friendly. There are a bunch of breakouts made though that help this and integrate a voltage regulator, power jack, pin breakouts etc. The NodeMCU dev board mentioned is one- Adafruit, Olimex, Sparkfun and RaysHobby also make them and they are much easier to use for hobby projects. I've had to use an ESP-12 directly for a project before due to space constraints and it was a hassle.
I'm curious, what exactly do you mean? Are you talking about wiring the pull-up's for an ESP-01? I was more thinking the SMD form factor packages like the ESP-07, which expose a bunch more pins but in a 2mm pitch.
> [Philips Hue Bulb] A $50 light bulb that requires a $60 base station, proving my point entirely
I'm not sure what this has to do with the article. Philips Hue uses ZigBee Light Link, not WiFi, and I'm pretty sure the steep price tag has nothing to do with hardware costs.
As for WiFi, it is exciting to see hardware like ESP8266 open up previously cost-prohibitive possibilities for hackers. My biggest complaint about using WiFi for IoT-related projects is the fact that every marketable WiFi-enabled device has it's own (often cumbersome) association/inclusion process. Perhaps that's a feature - enabling more options for wireless network security, but when it comes to user experience, the standard bluetooth pairing process makes WiFi association feel like pulling teeth for the average consumer. Maybe we just need a good WPS replacement.
I was mistaken on the ZigBee, thanks for the correction.
I will also agree that the setup is a pain in the butt for most of these things. I think that's why the Chromecast's and Dash's ultrasonic methods are interesting. Perhaps a low cost NFC one touch setup would be really cool, but any method I think of requires an extra app. But maybe that's not a bad thing?
Depends on the firmware. At least one starts up initially as an access point. You connect to it, hit a web page, enter your network credential, reboot and it's online.
I agree that setup for WiFi IoT products is a total pain. The simplest method I've seen is what WeMo uses...out of the box device is an Access Point, you connect, then enter your own network credentials...still takes a few minutes, but beats requiring another hub.
This could be so much easier if Microsoft hadn't f---ed up their Bluetooth Low Energy implementation in Windows.
BLE is a much better fit for a lot of these applications than WiFi, but by forcing users to deal with pairing, Microsoft has completely blown off its biggest advantage. Very frustrating from a device maker's point of view, and consumers literally don't know what they're missing.
They all have an ADC, it's part of the chip. It's just not broken out on all of them. It's also not that great, 10bit resolution is so-so and it only works for signals between 0 and 1V. This means you can't easily use for instance the awesome TMP36 temperature sensors with it. I mean you can, but you need something like a voltage divider (which adds error) and you need to recalculate the voltage to temperature conversion.
Yea, the Oak is probably the one that I'm the most excited about. I also backed one of Digistump's earlier kickstarters and was very pleased with both the hardware and the support.
Yeah, I've bought a few of their digispark chips. They're $8 and work great. This one's faster, has more storage, a few more bells and whistles, plus WiFi for $2 more. I can't not buy some.
I'm concerned about the TCP stacks on these boards. Near as I can tell, they're all built into the chips and no source code is available. Is my impression correct?
You can program the ESP8266 yourself. For its TCP stack it uses lwip which you can also compile yourself. The 802.11 stack is more of a black box though, but not necessarily the TCP stack.
What are the power requirements of WiFi gadgets compared to other wireless tech? I was under the impression that WiFi wasn't a good choice for embedded because it's so power hungry that it can't be powered for extended time on batteries? There aren't many places where I want tiny wireless things where I also have access to AC power. That's basically limited to sockets/switches.
I believe the peak consumption of the ESP8266 can hit 300-400mA when transmitting, so yea that will kill a small battery pretty quickly for a chatty app.
OTOH, if you can keep the device powered down most of the time and just wake up to fetch/report data occasionally, you should be able to get several months of life on battery.
Awesome to see this, I've had several of these nRF24L01's (ESP8266's) for a while with Arduino Micro's and some solid state relays to create my own automated light switching system. I also managed to create a digital AC dimmer for about £10 :) Phone -> Controller Dimmer -> Winning
The ones RaysHobby makes are pretty awesome too. They come with an RGB LED and LIPO power jack on board, plus they have the connector for an external antenna. Bit more expensive though ($16). He ships them with NodeMCU pre-flashed and the schematics are all open source.
No big deal, you can make it work. axTLS is a pretty lightweight TLS implementation that you could strap to your TCP framework and make it work fine. It's also BSD-licensed so you can put it in proprietary stuff.
i totally love the esp201. its very convenient to work with in eclipse/code blocks and can run C and C++.
the documentation is a bit sparse though but thats mostly no problem as theres a great community behind it.
But the biggest point for me is the size + the price. Why would one use a Raspi or Arduino to read out some moisture-meter if it can be done with a 3 dollar hardware piece the size of a fingernail?
The article is wrong (at least partially!) - the module they used (the ESP-01) only has a limited number of pins brought out, but the chip itself has a 10 bit ADC on board and there are plenty of modules that bring out the pins. I've been using lots of ESP-12 modules and they're great
Most of them are rather inconvenient to work with directly though, not least because they aren't breadboard friendly. There are a bunch of breakouts made though that help this and integrate a voltage regulator, power jack, pin breakouts etc. The NodeMCU dev board mentioned is one- Adafruit, Olimex, Sparkfun and RaysHobby also make them and they are much easier to use for hobby projects. I've had to use an ESP-12 directly for a project before due to space constraints and it was a hassle.