µC <-> WIFI, need some advise for selecting a WIFI module - Page 1
Forum section: electronics / projects

author: Pinkus
author_rank: Frequent Contributor
timestamp: August 05, 2018, 09:30:34 pm
content: May I ask your advice / opinions?I need to develop a microcontroller controlled device (8 bit, AVR or Pic), which occasionally (1-2x per day) should send status messages via e-mail. The device would run non-monitored 24x7. It should be connected to an internet router via WIFI to be able to send the mails.At first the low cost ESP8266 came to my mind, but I'm advised against it everywhere, because it has more hobby purposes as the target group and would not be reliable enough. Since a few thousand of the devices are to be produced, the solution absolutely needs to be reliable and also available in the long term.Hence the questions:Shall I integrate a ready-to-run Wifi module? Any ideas about which one?An alternative could be: Ethernet module driven by the µC with a RJ45 cable-connection to a WIFI router or WIFI range extender with an Rj45 socket (i.e. with built-in switch)?What would you advise?The parameters:8 bit or 16 bit µC (no Raspberry etc.) so an UART or SPI etc. connection would be preferredneed to be a cost-effective overall solutionIf you ever did such a solution, any of your ideas or remarks will be helpful for me.Thanks for any input in advance!

author: Phoenix
author_rank: Frequent Contributor
timestamp: August 06, 2018, 02:34:04 am
content: Since you intend to make and sell a bunch of these a pre-compliant wifi module (E.g. WF111) would be the way to go - they usually have SPI interface. A search on Digikey/Mouser brings up a lot of options, but I haven't used any specifically. In my experience ethernet is probably harder than wifi for circuitry, but wifi you need to consider how you will provision the device onto the network (SSID, ssecurity etc.). Then again you still have this problem with an external ethernet to wifi adapter, just one step down the line.

author: jbb
author_rank: Super Contributor
timestamp: August 06, 2018, 06:37:38 am
content: +1 for pre-compliance. It’s super expensive to qualify your own solution (easily >$5000, probably more). Also don’t forget the rest of the world.Note that the antenna is part of the certification. Using an external one gives better performance but might invalidate the certificates (e.g. a strong directional antenna).There are a few things to consider in the module choice in addition to certifications. These include supply voltage range, current consumption (in sleep, wake and RF modes), temperature range and the ability to host your own code.The WF111 is a bit old now. You could look at the Zentri modules from Silicon Labs (descendants). They have a low power ARM (?) core and you can compile your own code in. If you add a 32kHz crystal they can also do deep sleep and wake.

author: Pinkus
author_rank: Frequent Contributor
timestamp: August 06, 2018, 04:44:39 pm
content: Thanks for your inputs. The Zentri modules sounds interesting, I did not had them one on my list.

author: hamdi.tn
author_rank: Frequent Contributor
timestamp: August 06, 2018, 05:29:37 pm
content: Hi,I recommend ODIN module form U-Blox, it use AT commands so you can be easily used with an 8-bit or 16-bit uC.https://www.u-blox.com/en/product/odin-w2-series

author: cprosser
author_rank: Contributor
timestamp: August 06, 2018, 11:00:30 pm
content: I have only used their products for hobby stuff, but the Particle product line looks good for this unless the part cost is too high. They are structured for commercial.https://www.particle.ioSent from my iPhone using Tapatalk