New u-blox TOBY-R200 Firmware and CID Issues

Aleksander Morgado aleksander at
Thu May 30 07:36:54 UTC 2019

> It looks like ModemManager takes the highest numbered CID it sees and assumes it needs to use the next one available or if at the max CID then reuse it.  In the case of the TOBY-R200, only CID 1 and 31 are used so ModemManager tries to reuse CID 31 but the modem reports an error since it won't let this CID be erased/overwritten.  Then ModemManager tries to connect to search for the PDP context that it just tried to create and fails the simple connect.
> It seems that ModemManager does not use the CIDs 2-30 or even try to.

Yep, this looks like something easily fixable. If the highest CID is
used, we should look for an unused one starting at 1 again.


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