MangOH Red IoT Input UART


#1

Hey guys,

I’m looking to communicate through the IOT card’s UART and am following the schematic, I see that runs to a couple of different places. Most notably the WiFi module. I intend to use the bluetooth and also need to communicate over UART.

From the research I’ve done it appears that I need to send the following AT command: AT!MAPUART=17,1. However, I’m worried that I would then be blocking the bluetooth when that’s available.

http://legato.io/legato-docs/latest/howToCustomizeUART.html

Is there a sample repository that demonstrates communication over UART with a MangOH?

Thanks very much


#2

Bluetooth is over SPI, so there is no issue.
You can use the UART for IoT.


#3

Note the SPi is one we create using USB to SPI converter. So you can also use SPI on iot


#4

Thanks Ashish, I realize now that the level shifter in the schematic is not turned on by default, so there wouldn’t be intersection with the Wifi module. However, if someone wanted to use the wifi/BLE module and UART this level shifter would be on and the UART signal would then funnel to the Wifi module? Or is this Wifi UART only used to download firmware to the Wifi module if it’s in a bad state?

Also, was my above listed AT command correct to get the IOT UART online? Do you guys have any sample code that shows reading and writing over the UART? I see the LE_TTY api on legato, but I’m still not clear on how I would communicate with my external device and receive its feedback. http://legato.io/legato-docs/latest/c_tty.html


#5

the UART connection between WiFi and CF3 module is only backup and not activated by default.
For taking between CF3 and WiFi, we have the SPI interface
CF3->CP2130->WiFi.

Let me get back to you on the UART interface.