GL 6110 modem hang

We are using GL 6110 with USB connected to our software on Linux (kernel 3). We face a few problems.

  1. If we send SMS continuously (eg 10 or more SMS), the modem would enter a state of not ready for command.
    Modem would show ERROR 512 before becomes not ready for command.

  2. If the modem was sending SMS and a few SMS was received (at the same time), the modem would enter not ready for command state. Modem status: “CPAS: 1”

  3. We are encountering another strange problem with the Wireless Sierra modem. The modem would become not ready for command for no known reason. The modem would return status “CPAS: 1” (not ready for command). This happens during the modem was idle or not sending or receiving of SMS.

We do notice, the previous batch modem was shown as “WAVECOM WIRELESS” when we check the modem info, while the current batch is showing “Wireless Sierra”. We like to know if there are any differences in the chipset/behaviour?

We have been using GL modems for the last 4 years.

Any insight is appreciated


What firmware version are you using (at+cgmr)?

There has not been any hardware change over the lifetime of the GL6110 so it is not down to this. The change in labeling is just down to the fact that Sierra Wireless bought Wavecom.



Hi! The firmware:

GL6110 Product R7.47.0.201202010317.GL6110 2221420 020112 03:17

Please advise




This is a pretty reliable software release, it has to be down to something else in your system i.e. the SIM cards you are using have they change to being LTE capable, this can affect the unit since the SIM puts more demands on it.

I suggest you talk to your commercial channel to give you some proper tech support.



Hi together,

nice to see that i am not the only one who still sends SMS with these modems :wink:

I expected the same issue - the problem seems to be when sending some batch of SMS (around 10) and receiving answers to them at the same time screws the modem up. Normaly i do AT+CMGS … then the PDU code and CTRL+Z. Then the modem should answer +CMGS: 230 (or some number). But in case the problem occurs, just nothing happens. The only why to get the control back is to send AT+WAC two times.
My “hotfix” for this was to wait about 4 seconds after sending each SMS until sending the next one.
I have the feeling that this is a firmware issue because i use GL6110 and also an older FXT004. The FXT was fine with older firmware, but with 7.47.6 i have exactly the same issue like also the GL6110.