AT Command Set

R

regardtv

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Hello all,

I'm interested in learning more about my modem's AT command set.

ProAsm - from what I've seen you must have access to the command set - is it an extended set or standard AT ?

Any references ?

Me wanna play a bit ;-)

R
 
http://rodent.za.net/MyModemCommands

Those are the ones I've documented/tested so far.

The modem implements a <i>very small</i> subset of the "3GPP TS 27.007 AT command set for 3G User Equipment (UE)" standard, available from http://www.3gpp.org/ftp/Specs/html-info/27007.htm

Some of the commands are used for different purposes rather than the recommended use, e.g. the AT+CGATT command.

Let me know if you discover anything else, so I can add em.

<center><h5><font color="red">Oo. MyWireless <s>Hacks</s> Tweaks & Tech Info.oO </font id="red"></h5><h6>Have you checked the fawking FAQ?</h6></center>
 
Here you go RoDent [:D]

AT+CEER
Responds:
+CEER: Modem cable disconnected

AT+CGDCONT
Responds:
+CGDCONT: 1,"PPP","sentech.co.za","username,password",0,0

AT+CGDCONT=1,"PPP","sentech.co.za","Newuser,Newpass"0,0
Responds:
+CGDCONT: 1,"PPP","sentech.co.za","Newuser,Newpass",0,0

AT+CGATT=1,2530000
This will accept and respond with the new frequency but still the modem uses the old one [:(]
Needs working on [:)]

AT+CLCK
Responds:
+CLCK: 1,7

AT^C1
This will hard reset the modem, but stays in a hung position for some reason.


<hr noshade size="1"><center><font color="blue">MyWireless Stuff</font id="blue">
<font size="1"><font color="black">The opinions expressed here are mine alone and do not necessarily reflect the opinions of my employer</font id="size1"></font id="black"></center>
 
Yeah, ProAsm, I haven't gotten round to documenting some of these yet.

AT+CEER
This is used to get the extended error, after a "NO CARRIER" message.
This is where extra errors such as "NETWORK NOT AVAILABLE" and stuff comes from. You can use this to get the last verbose error message if a command failed.

AT+CGDCONT
Yep, I've updated my linux chat script already with this one. This is essentially the modem "flashing-with-username-password-on-Windows" that's required for PPPoE and Linux, that I was talking about. Will document this one.

AT+CGATT=1,2530000
Yeah, I've fooled around with this one quite a bit. I've managed to convince the modem at times to lock onto a specific tower, but only after lot's of fiddling. The exact set/sequence of commands is a bit unclear. I know I had to force it to detach from the network by doing AT+COPS=2 (deregister from network) and then fiddling with the frequences, but it was all a bit fuzzy.

AT+CLCK
This is the facility lock. You can basically disable Sim card PIN prompting and login prompting with this, apparently. But seeing as we don't use sims, it's pointless.
AT+CLCK=? will return the list of supported "facilities" that can be locked.
Don't think I'm going to bother with this one, since it's not required on our network.

Other, new ones:
AT+CPOST will return a hex number indicating the results of the power-on-self-test.

AT+GCAP: return the modem command capabilities. This will list a few of the extended +G commands that the modem supports.

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">
AT^C1
This will hard reset the modem, but stays in a hung position for some reason.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Yeah. That puts the modem into "firmware download mode" :) It expects hex encoded firmware data after that command's been sent.

Here are some more firmware related commands, that can be used after AT^C1 has been enabled.

AT&T13 will return the firmware download packets size.
AT&T3 will start the download
AT&T4 is used to ship down hex-coded download packets.
AT&T7 reboots.
AT&T6 aborts the firmware download

<center><h5><font color="red">Oo. MyWireless <s>Hacks</s> Tweaks & Tech Info.oO </font id="red"></h5><h6>Have you checked the fawking FAQ?</h6></center>
 
Thanks on the AT&T - was wondering what they did.

Regarding the AT+CGATT=1,2530000 - yeah we need to work on this one as it could benefit a lot of people.
Unfortunately time is a problem, I've hardly got ontop of Phase I and was informed an hour ago Phase II is upon me [:)]

I seem to remember doing a AT+CGATT=0,0 first then the next one and there was also another command (will get it when I get home) that I used, but still the friggin modem locks onto the original frequency that was stored.
There must (has to) be a way [;)]


<hr noshade size="1"><center><font color="blue">MyWireless Stuff</font id="blue">
<font size="1"><font color="black">The opinions expressed here are mine alone and do not necessarily reflect the opinions of my employer</font id="size1"></font id="black"></center>
 
Hello,

ProASM & Rodent - I'm not going to re-invent the wheel and write my own connection manager - if it's delphi pass the source and I'll help - otherwise I've found what I find to be a pretty reliable way to tower surf/search... I cannot force a tower but at least I can let the modem hunt for a signal - this will solve my and other's problem for getting kicked off and then connecting to an incorrect tower.

Ok, specific channel selection isn't so easy. but an easy way to reboot the modem to allow for channel searching:

Check tower details: at+cgatt?
If it does not match tower do a reset: at^c1 &lt;cr&gt; at&t7 &lt;cr&gt;

Ok, so we're rebooting... diconnect com port and sleep 5 seconds. Try process again until we find the correct tower.


She reboots happily and works well.

Not ideal but it's a start.

Rig
 
Hiya, RegardTV. Yeah, that's a "brute force" way of rebooting it heh :)

I know that a search can be inititiated with

AT+CGATT=0
AT+CGATT=1,0
AT+CGATT=1,2506000,2518000,2530000

But it doesn't always latch on to the strongest tower then. The modem seems to be a bit greedy when it comes to "latching on".

Perhaps ProAsm, can add an option to the dialer "Force correct tower" that'll do this little jiggy, or yours.



<center><h5><font color="red">Oo. MyWireless <s>Hacks</s> Tweaks & Tech Info.oO </font id="red"></h5><h6>Have you checked the fawking FAQ?</h6></center>
 
Well, you could like take down the tower details if you connect to one you're happy with, then insert those details in the connection thingies you guys are talking about and make the modem lacth on to it, if not, retry till it does?

or am I not getting it?
 
Hello Noone,

You're getting it ;-) It's just that the modem doesn't always GET IT;-)

I presonally have a VERY fun problem. Both the towers that talk to me I'm on the 0-120 deg sector - so both are on the same frequency. Makes my tower selection really ff*8ed.

In the mean time I'm progressively working through the UMTS AT spec... slow, boring and not all that intuitive ;-)

R
 
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