HL7800 - +KSUP reported 154s after wakeup

As the title suggest it took 154 from assertion of wake-up pin until the KSUP URC.

How can this happen?
The AT reference manual says the default maximum time should be 4000ms, right?
We’re running FW 4.4.6.

Thanks in advance

Hi Martin,

KSUP is returned in case the module boot successfully. It means that all subsystems (modem and application subsystems) initialized.
For the time you mentioned, it is the timeout in KSREP, right?
The timeout in KSREP is used for activating UART configuration.
By default, the timeout is 4000ms, it means that after 4000ms if all subsystems have not initialized yet, the UART interface will be enabled (CTS is high), but KSUP will not be returned, it returns only when all subsystems initialized.
Note that: the timeout in KSREP is implemented from FW4.5. So please update your devices to the latest firmware.
You can refer “AirPrime_HL7800_Low_Power_Modes_Application_Note” document to understand the subsystems of HL7800.



Thanks for your answer.
As of now we’re not in the process of updating our FW.
What is the timeout in FW 4.4.6 - How long should our application wait for +KSUP after asserting the wake-up signal?
What makes this issue more problematic is that if (for some reason) the module is not in hibernate (+CEREG != 4) when we want to wake it up, the KSUP is not communicated. That means if we have a timeout of, lets say 155 seconds, when waiting for +KSUP and the modem is not in hibernate - we will wait for 155 seconds needlessness.

Best regards

Hi Martin,

In fw4.4.6, there is no timeout. When UART configuration is initiated, the CTS will be high, and when all subsystems are initiated successfully, KSUP will be returned.
We have tested many times in our devices, and the time for KSUP is about 2-4s after we asserted the Wakeup pin.

Could you help to re-check your device?
It should be great if you could provide the CLI log.
You should check the signal that is used to assert the Wakeup pin.
We suggest re-flashing your device and check the scenarios again. If the KSUP is still returned too late, please contact your distributor or send Sierra the information through “Contact Us” on “sierrawireless.com


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