I would like to use the GNSS functionality on HL7802. I am connected to a MQTT broker via TLS where I can set the ping period to a couple of minutes. I figured that it may be possible to use eDRX and keep GNSS receiver active so that it uses the internal RF resources every time the module is in eDRX…

Hi and thank you for the link. I think it does not address my questions completely. There is no mention in that post whether the GNSS resumes automatically when module enters eDRX sleep. I can only assume that it does. The post says that GNSS can be enabled in PSM sleep mode and Idle-DRX/eDRXmode…

HI @jakub.polonsky , Power Saving Mode (PSM) is a 3GPP feature that allows the HL78xx to minimize power consumption by registering on a PSM-supporting LTE network. It is not available on 2G networks. You can refer to Section 3.3 3GPP Power Saving Features on page 25 of the HL78xx Product Technical …

Thank you. So if I get it correctly, there is no way to use some sort of a power-saving scheme where the modem would keep network registration and TLS connection open under 2G and at the same time operate its internal GNSS receiver. This is only supported in LTE.

GNSS with eDRX and 2G fallback

IoT Modules HL78

jerdung September 7, 2022, 9:16am 2

Hi @jakub.polonsky,

For these questions, you can refer to this topic: GNSS stop to work

Thanks,

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GNSS with eDRX and 2G fallback

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