WP7700 AT command Interface over UART using MangOH Red


#1

Currently, I am developing some embedded software for a host controller to handle setting up a data call on the WP7700 and have had some weird results. When I ssh into the WP7700 and use the Legato terminal, I am able to setup a connection every time (5 of 5). When I use microcom over the Legato terminal to send AT commands, I am able to setup a data connection every time (5 of 5). When I try to dial out with the AT command interface over UART lines from our host controller, I cannot setup the data connection (0 of 5). I can successfully set up everything and then when I try to dial out (ATD99**1#) I get an ERROR. The interesting part comes into play when I open microcom to the AT interface via the Legato terminal and then try to dial out over the UART lines, I can do so successfully. Is there something that is blocking me from dialing out over the AT command interface over the UART without being connected to the Legato terminal? Thanks for any help in advance.


#2

you need to transfer the UART to AT port
https://source.sierrawireless.com/resources/legato/howtos/customizeuart/


#3

I have done this and successfully sent other commands over the UART (turn on radio, check out SIM, setup PDP context, start and check GPS), but get and error response when I try to dial out to a data connection over the PDP context (ATD99**1#), but when I do the same commands over microcom when I am ssh’ed into the WP7700 I can connect without an issue.


#4

The commands may not work via the UART using an external microcontroller. I tried to setup a TCP connection with an external microcontroller with a WP chip, but it is not enabled in the firmware. They are meant to be used as an application processor. This could be what you are running into, but need to have someone confirm?