[Darrell Jefferson]

Thank you, Lonny. I recognize the confusion you speak of. All of the recent experiments have used the EV3 modem. But we have switched back and forth between the drivers for MTSMC-EV2 and MTSMC-EV3 in our attempts to get this thing working. Previously — just to be sure our application was written correctly, we briefly switched to the EV2 modem and verified that we were able to go online using either environment. (we were)

I have opened a ticket with support, as you suggested. Thank you for your help.

[Darrell Jefferson]

Hi — I work with Lucas on this modem development, and I have some more information to add to the puzzle.

The most confusing part is that we have two different environments attempting to use this same N3 modem on a Sprint account — 1) Ubuntu 12.04 with our application calling pppd, and 2) Embedded XP using Multitech-provided drivers and making the calls through RAS. What confuses me is that the Ubuntu environment successfully goes online with the modem *every* time — and the XPe environment fails *every* time!
I have verified that all AT commands issued to the modem are identical between the two environments (up to the point where the dial string is handed off to pppd or RAS) … but the result of the Dial operation are just different between the two. I have logs to show that the sequence “appears” to be the same up until the dial operation.
I can’t understand how the modem would respond differently to the type of system on the other side of the serial connection. We are using the exact same hardware in both cases (I just swap out the compact flash card to load one operating system or the other).

Under XPe I have tried using the Multitech-provided MTSMC-EV2 and the MTSMC-EV3 drivers, but that didn’t make any difference. The Ubuntu environment issues the following sequence just before dialing …
AT+WOPEN=1
AT+WOPEN=5
ATD#777
And if I try that same sequence under XPe, the result is…
ERROR_AUTHENTICATION_FAILURE

Should we just give up because you say N3 doesn’t work with a Sprint account, and chalk the different behavior of the two operating systems to some post-dial activity (we don’t directly control either pppd or RAS once the hand-off has occurred)

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