KSUP notification fails on RC7611


I enabled KSUP notifications, but I get it correctly only on RC7620, but not always on RC7611. Both have official R9 firmwares. But when I have a SIM card in, the notifications work on both modems. Only when there is no SIM, the notification is not found on RC7611. Is there any hardware issue/difference between the modems?


this is known issue.
It is fixed after FW SWI9X07H_00.08.24.00.
FW R9 of RC7620 is after this version, that is why you don’t see such problem in RC7620.
You need to wait for next release of RC7611.

But I have a test version of R10 from Sierra, for RC7611 and it is still same with that FW as well!

Manufacturer: Sierra Wireless, Incorporated
Model: RC7611
Revision: SWI9X07H_00.09.10.00 85890e jenkins 2023/09/25 03:16:56
IMEI: 358026262490496
FSN: CV3306753016B1


Who gave you this FW?
then have you reported this to him/her?

We noticed this issue only yesterday. We usually always have SIM card and KSUP notification works fine when there is SIM. But wanted to check here as well, just in case we are not missing something fundamental. We have now reported to the concerned.

the test is straight-forward:

// Start up with no sim inserted

Manufacturer: Sierra Wireless, Incorporated
Model: RC7611
Revision: SWI9X07H_00.08.24.00 cb6ed3 jenkins 2022/01/07 03:05:21
IMEI: 352138110012345
FSN: 6M941280112345


Legato Ver: 21.09.0.ThreadX.rc4
Yocto Ver: unknown
OS Ver: 21.09.0.ThreadX.rc4 cb6ed3 jenkins 2022/01/07 03:06:32
LK Ver: unknown
RootFS Ver: unknown
UserFS Ver: unknown
MCU Ver: unknown
TAOP Ver: TZ.BF.4.0.C6-00126


+KSUP: 2  => SIM card is not present

+SIM: 0

+SIM: 1   => SIM card is inserted

Yes, this is how we test and we get +KSUP: 0 when there is SIM, but not +KSUP: 2 when there is no SIM

Update: We increased timeout from 10s to 15s and we got the notification. When SIM is inserted, we typically get notification within 2~3 seconds! How much is the typical delay between the time the /dev/ttyUSBs show up and the modem sends KSUP to inform that it is ready to talk to ?

i suggest you to take some more SIM card to do some benchmark

Another way is to use AT+CPIN? to confirm if SIM is inserted

BTW, how is the time taken for your test on RC7620?

The issue is that we are dependent on KSUP to know when is it the right time to talk to the modem, even AT commands. So checking AT commands is not really what we are after. We do not want errors from modem at start. We want some notification from modem and only then we want to start talking to the modem. In RC7620, we usually get the first notification within 2~3 seconds when there is SIM.