RN131/171 wifi modules with embedded tcp/ip stack

[djlorenz]

Hi guys,
i'm working on a little project and i'm looking around for wifi communication for my board.
i had a look around the microchip tcp/ip stack but it's a little bit a mess for me....

so i found these:
http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en558370
http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en558369

all in one, easy config trough usart and ascii characters, a lot of breakout boards around... should be nice to use them!
unfortunately there's a big lack in documentation... on details microchip talks about UART & SPI, RN131 datasheet talks only about uart, RN171 says:

High throughput: 921 Kbps TX, 500 Kbps RX data
rate with TCP/IP and WPA2 over UART, up to
2 Mbps over SPI slave

but in both of them no mention to SPI configuration / no pins on pinout... nothing!


in future expansions of my board i'll need to transfer some audio stream... so i'll need to be on high throughput and 500kbps should not be enough...
have anyone of you tested this products? any info about SPI? any "easy-to-use-" modules? i had a look to CC3000 from TI but seems to be more difficult to configure and they have libraries olny for TI mcus...


thanks for your reply!
Lorenzo

[RABeng224]

I have used the RN-171.  It took a little bit to become familiar with but all in all it is working out OK.  As far as SPI is concerned, you have to run a "beta" firmware on the module.  You lose a lot of GPIO and the functionality that comes with them (auto connect, link status, etc...).  We ended up going back to uart with flow control.  With regard to throughput, I would look into using the GPIO for auto connect and link status.  This saves a lot of time compared to having to enter command mode and send the serial command to connect to TCP every time.  Also, use as big of serial buffers as you can and use the UART flow control to throttle the data from the module.  We are running over 115k baud with uart circle buffers around 128 bytes each.  Our application is far from audio streaming though.

R

[djlorenz]

I have used the RN-171.  It took a little bit to become familiar with but all in all it is working out OK.  As far as SPI is concerned, you have to run a "beta" firmware on the module.  You lose a lot of GPIO and the functionality that comes with them (auto connect, link status, etc...).  We ended up going back to uart with flow control.  With regard to throughput, I would look into using the GPIO for auto connect and link status.  This saves a lot of time compared to having to enter command mode and send the serial command to connect to TCP every time.  Also, use as big of serial buffers as you can and use the UART flow control to throttle the data from the module.  We are running over 115k baud with uart circle buffers around 128 bytes each.  Our application is far from audio streaming though.

R

that's a big help! Thank you!
where did you find about beta firmware? i've checked out with google, on forums, on specs... nothing...
maybe there is a "configuration/programming" guide i didn't find?

my wireless stream need to be fast and with really low delay. that's why i wanna go to spi.
we are also thinking about a mp3 (or other formats) hardware endocder/decoder to reduce the data stream but i don't know how can it takes to encode/decode...

[RABeng224]

Here is the "beta" firmware we were sent from Microchip.  Included in the zip is the new firmware that you need to program the module with.  Also in the zip is a pdf on the protocol and the connections.  Hopefully it helps you out.  Like I mentioned earlier, we ended up going back to UART.

R

https://dl.dropboxusercontent.com/u/3552756/Public%20Engineering/2977wifly-SPI-2.22e.zip

[djlorenz]

i'll have a look but i think we will go to the TI device... seems to be more difficult to program but faster...
i'll let you know
thank you so much for the files!

if anyone tested other modules?