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Comment by ldng | Hacker News Reader

Can someone clear up if the modem and the GPS can talk directly? Not being able to shutdown the GPS indepandently put me off librem.

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Perhaps it would be better to say "Not being able to run the GPS with the modem shut down"?

If the modem is on, the carrier can figure out your location relatively precisely from your transmissions, even if GPS were disabled.

So the real loss is that you can't use the device for navigation/mapping without turning on the modem.

Right?

At least this can be resolved by using an external receiver.

I believe modern cell standards use either NAVSTAR or base station broadcasts to synchronize time slots, adjust beam forming parameters, arrange call tower handovers and such to provide Tokyo or New York or Delhi relevant density capability, and thus GPS functionality is a requirement, apart from convenience of whether it’s available to userland runs in application processor.

Virtual UART drivers for every phone since 3G HSDPA creates GPS NMEA ports on your PC and it spits it garbage when it feels like doing.

The GPS is on the modem SOC, as I understand. Perhaps they should leave the antenna unconnected. Then use an additional GPS module?

Looks like it's on the SOC (SOC has it and not seeing external GPS chip on board pictures), so most likely.

Ask them on twitter @thepine64 Though how the SOC is wired up inside may beyond their scope or the dreaded NDA from the SOC supplier.

https://wiki.pine64.org/index.php/PinePhone

Looks like GNSS is directly on the modem chip.

The GPS is done on the EG25-G modem and can't be switched independently.

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