Which ESP8266 module to try?

Projects Networking, Protocols, and Devices
1

My most recent wifi experiences have been the Arduino wifi shield and digi xbee wifi. They are so much more expensive and the xbee wifi is merely a serial port replacement. So I'm interested in trying out ESP8266. After some ebay searches, I found there are generally two types of modules:

This one has two separate chips and no ESD shield:

Then there is this other one with ESD shield and FCC:

I wonder which one I should try. I imagine the second one is newer, got FCC certified (?!) but both need voltage level shifting, right?

2

liudr:
My most recent wifi experiences have been the Arduino wifi shield and digi xbee wifi. They are so much more expensive and the xbee wifi is merely a serial port replacement. So I'm interested in trying out ESP8266. After some ebay searches, I found there are generally two types of modules:

This one has two separate chips and no ESD shield:

Then there is this other one with ESD shield and FCC:

I wonder which one I should try. I imagine the second one is newer, got FCC certified (?!) but both need voltage level shifting, right?

I would recommend the ESP-12F. The F version has a 4MB Flash chip, so you can have 1MB for code and 3 MB for storage, OTA reprogramming. There is a GitHub project that integrates them into the Arduino environment.

With the '12F you have to supply it with 300mA of 3.3V and you need a FTDI serial converter to program it.

Chuck.

3

Thanks. I assume the second one is 12F? I just ordered a wemos D1 R2. It's cheap enough and can be programmed with Arduino IDE. I'll experiment it a bit to see what it can do.

4

I second the ESP-12F as well, it's the upgraded version of the ESP-12E. On Aliexpress, it costs as low as $1.70 a piece. Don't forget to order some adapter plates too, for ease of connection to 2.54mm connectors or wires.

5

Thanks. I ordered this wemos board, which looks like an arduino uno with all necessary adapter and power supplies:

What I am concerned with is the level of support. You could have a linux single board computer for $8 with quad core processor and 1GB ram but then when asking questions online, you get nearly zero response.

So for someone just starting programming the ESP-8266, any recommendations for resources?

http://www.wemos.cc/

This place only took a little while to entirely read through. There are sample codes for arduino IDE but I don't know how much I can expand beyond the samples before hitting some hard wall.

6

Yeah, don't bother with those ESP-01 modules(the first one). It's worth spending a little more for the ones with more flash. I have both, but prefer the WeMos D1 Mini to the WeMos D1 R2 because it's way smaller, cheaper, and has pretty much the same capabilities.

liudr:
both need voltage level shifting, right?

They do have 3.3V I/O. There's been a lot of discussion of whether the datasheet indicates they are 5V tolerant or not. My take has been that if it was actually 5V tolerant then of course the manufacturer would clearly state this since but we know that Espressif is not so good with documentation.

There was an article on Hackaday that had a ton of comments on both viewpoints but didn't provide any actual proof of 5V tolerance. Someone shared it to the ESP8266 group on Facebook and a user named Teo Swee Ann commented:

i can reply officially here: it is 5V tolerant at the IO. while the supply voltage is at 3.3V.

The name of the Espressif CEO is Teo Swee Ann but of course there are lots of fake names on Facebook and people with the mentality of 12 year olds and too much time on their hands who think trolling is funny. Why should we need to find some obscure facebook post to get this cleared up? In fact, there is a post on the official Espressif ESP8266 forum by one of their employees:

IO and digital power supply of ESP8266EX ranges from 1.8V to 3.3V.

We donot recommend you to apply 5V to IO.

Such a great module but I don't understand why these Chinese manufacturers are so bad at documentation. I get that there is a language barrier but people have looked at the datasheets in Chinese and there is no more information. With the budget it takes to develop and produce a product like this it should be insignificant to pay someone to write proper documentation.

liudr:
So for someone just starting programming the ESP-8266, any recommendations for resources?

There's a strong ESP8266/Arduino community that has done a ton of work to make using ESP8266 easy but compared to AVR it can be very frustrating. The ESP8266 Arduino core is great but the library documentation is super lacking. They basically expect you to just look through the source code and figure it out. There also seems to be more than the normal amount of bad tutorials, etc. out there so you really have to filter through the information you do find. Even simple things like trying to get specs on the ridiculous number of variations of those modules is extremely frustrating.

ESP8266.com forum: For some reason I've never found any useful information on there. They are so greedy with the ads that every thread ends up being 20 pages long. I get that these sites need to support themselves and I don't mind ads if that's what it takes to keep them going but there's such a thing as going too far, they went way too far.

https://github.com/esp8266/esp8266-wiki/wiki: not really that great

https://github.com/esp8266/Arduino/tree/master/doc: You can find some useful information on the core if you browse around in there

http://bbs.espressif.com/viewforum.php?f=64: There are a couple of employees on there giving official answers but you're not going to find any Arduino-specific information.

https://nurdspace.nl/ESP8266: meh

7

travis_farmer:
I just purchased some of THESE this morning, sadly without asking for advice first. are they OK to experiment with, or did I waste my money?

I will likely have to buy some shields or level-shifters, I'm sure.

(this is what happens with very early morning impulse buying)

~Travis

The will work for a Wifi adapter, but you will not have much expansion ability. no SPIFFS, only GPOI0,2

Chuck.

8

Some of those modules have a 512kB flash chip which is not large enough to update to any recent AT firmware version(I think the last one that will fit is 0.50). I seem to remember someone saying the black ones have more flash than the blue ones, you could probably look up the part number on the chip next to the ESP8266 chip to see what it has. Even if you can't update the firmware it doesn't mean the module is useless. Most any sketch or library you find for it will work with the older firmware. As chucktodd said, those modules are best suited to provide WiFi communication to a regular Arduino board. GPIO and extra flash really aren't necessary for that application.

9

I wouldn't consider $6.75 for one of those modules low cost but on the other hand I've been waiting on some of my cheap ones shipping from china for almost 2 months now so I guess it's worth paying a premium to get them from in-country sometimes. It's weird because some of my China orders show up in like 3 days, often days faster than orders placed to US companies only a few hundred miles away from me, but it seems like whenever it's something I really need China lags.

10

I usually go to banggood.com
They have US stocks for some of their stuff. Just got my WeMos board from them yesterday and had a play with it. It's got potentials, if there are good references and documentations.

11

banggood doesn't have the WeMos D1 Mini, maybe just out of stock, but that is an excellent price for US stock if you have a use for one of those D1 R2 boards. Considering the low prices, the documentation on their website is excellent, best I've seen for this sort of thing. They even have the boards incorporated into the ESP8266 Arduino core. I have a D1 R2 and my only complaint is I bought it accidentally because it was advertised as a shield(they've fixed the listings now). I didn't look close enough at the pictures to see it was a standalone board. I've only used it a couple of times because I prefer the D1 Minis but it worked fine for me.

My D1 Minis showed up a couple of days ago, I was starting to get nervous but I actually have found shipping from China to be reliable if unpredictable as to speed.