Suggestions on Wifi module integration with PIC18 Family?

wirelessage · Joined: 08 Aug 2012 Posts: 34

Hello all:

I would like to know if any of you have recently integrated a wifi module with PIC18 Family.

We have a firmware that does not have an OS. Its a PWM driver with a bunch of sensors activities. We need the Wifi module to get/set on average 256 bytes of data every second and occasionally get/set 1500 bytes of data to/from the host.

Would appreciate any information on wifi modules that have been successfully integrated with the PIC18 Family.

Would prefer for the Wifi module to shoulder most of the load, and the Host (pic18) to just communicate with a SPI Driver with a simple command structure to set and get data.

Thanks!

Ttelmah · Joined: 11 Mar 2010 Posts: 19513

Look at the ESP8266.

Gabriel · Joined: 03 Aug 2009 Posts: 1067 Location: Panama

I don't think the ESP8266 will give you the bandwidth you need.
Setting up the connection with the default AT Commands take a little while... furthermore establishing the connection via the internet to a server and for that server to manage your request takes time too... so that 256 byte/second might not be possible.

It is an unbelievable chip though.... easy to work with.. gets you online in minutes.

G.
_________________
CCS PCM 5.078 & CCS PCH 5.093

Ttelmah · Joined: 11 Mar 2010 Posts: 19513

256 bytes per second is easy for the 8266. The default baud rate is normally 115200, and it manages close to this on the WiFi.
If one was asking for over 10000 bytes per second, then something else might be needed, but I've used these sending logging packets using over 2000 bytes per second without problems.
The actual chip can manage several Mbps....

wirelessage · Joined: 08 Aug 2012 Posts: 34

Ttelmah,
Thank you (as always) for your feedback! Glad to hear that you have used the ESP8266 and it is working well for you. This is what I wanted to hear.

Gabriel,
Thank you for your input! Seems like you are looking at the time for initialisation in the connection as well... It is ok for the device (in my case) to initialise and take more time to come to a steady state and then start sending and receiving data.

As a follow-up question, I would like to know your opinion to develop this as a product. I am looking more from a standpoint of technical support. I went to ExpressIf website and they have documentation, but there is no apps team here in USA to help us out with any questions. Primary help is documentation/forums. Want your thoughts on your experiences with ESP8266 and need for technical support.

Ttelmah · Joined: 11 Mar 2010 Posts: 19513

I open a connection and keep it open. However before sending, I will poll if the connection is open (It'll drop sometimes with spikes, or other things going on the network). I then try to re-establish is this has happened.
The actual establishment can take a few seconds (depends on how fast the DHCP server is, and the connection itself). However with chips like the DsPIC's there is enough RAM to buffer while this is happening.
Assuming a large PIC18, the same should be true.
I've had systems go weeks without dropping even once, but then you get something like another radio connection on the band, or noisy large electric motors, that can cause multiple drop outs....

wirelessage · Joined: 08 Aug 2012 Posts: 34

Thank you Ttelmah!

Hoping to hear from others on their experience with integration with PIC18 Family.

benoitstjean · Posted: Sun Mar 04, 2018 3:36 pm

You can also look at the Lantronix x-Pico WiFi. Very small, more expensive than a 3$ ESP but not the same ballgame. I'd say the ESP is more for hobbyists as opposed to the Lantronix devices which are meant more for commercial / industrial uses.

Ben

asmallri · Joined: 12 Aug 2004 Posts: 1634 Location: Perth, Australia

benoitstjean · Posted: Tue Mar 06, 2018 8:59 pm

I guess I didn't explain myself correctly. But you're right.

The ESP8266 is cheap to buy and many companies produce "ESP boards" which are sold everywhere (ebay, Sparkfun, Digikey etc) although the ESP8266 IC is made by Espressif. But the dev boards or modules it is mounted-on is mass produced by multiple companies. But xPico is made by Lantronix and is more than a single-chip solution and I don't think kock-offs or spin-offs exist.

When I said "hobbyists", it's because a hobbyist will not mind spending 3$ on a wifi module (ESP8266) to add to a circuit but may not want to spend 25$ for a different module (xPICO).

A good analogy is Android and Apple. Products running on Android are made by different companies and are usually cheaper than Apple but iOS is specific to Apple and are usually more expensive.

So Android would be the "ESP8266" equivalent and Lantronix would be the "Apple" equivalent.

For sure, the ESP is the cheapest solution.

Cheers!

Ben