X-Post from r/linux: An electrical engineers opinion on the Librem 5


#21

I believe I read somewhere that optionally you could choose between a SIM and a micro SD or 2 micro SD if you didn’t want / need the SIM


#22

You did but I think it was just someone’s future fantasy, not functionality available now. Maybe this: Primary drive: Dual SD cards in RAID 0

So you can take the modem out but you can’t realistically use that M.2 slot for anything else. (That’s not the SIM slot though, which is different but related.)


#23

You can take out the M.2 card that holds the cellular modem, and put in something else, but that M.2 slot is probably only wired for USB (not PCIe), and it also might involve changing some code in the kernel to allow it. This is a question for the Purism engineers to answer.


#24

No, that’s a different idea to what was in my head… I vaguely feel like it was maybe something Todd said in one of TLG’s videos… I’m skimming them now to try and find it shrug if I was wrong, thank you kieren and amosbatto for clearing up the complexities for me

edit: just re-watched the video and he didn’t mention it where I thought he did, so I now have no idea where the idea got into my head :stuck_out_tongue:


#25

@tommes, here are two links to information about MDM9607.LE.2.2 modem firmware that IMO are worth of mentioning (as you already pointed out):

And IZat is probably there as part of Qualcomm® Trusted Execution Environment.


#26

Just need to wait some news from Purism about these issues. I think it’s really too complex for us.
If there are some issues some people can probably help them. This planet is big and some smart people help other for create an open source world and increase privacy :wink:


#27

I am not Verizon customer, but according to this good news and to this bad news how it is possible that the very same firmware from Verizon once supports voice and in second scenario not, even though it is about the same firmware for the very same parent module? Basically I just wanted to link to those for your awareness as it looks like that (might be) EG06-A exists (on the particular market) as Telematics version and EM06-A as non-Telematics (Data-only) version. Just hypothetical question here, as I don’t understand, is it about EG06/EM06 modules for Verizon having some voice supportive chip (hardware) difference or just about disabling voice on M.2 card using software (and perhaps some preferable doctrinal rules)?
Secondly (and maybe somehow bothering), I like to point to Sierra Wireless AR7592 as this brings us to other modules that are just like AR7592: EMEA - AR7594, China - AR7596, Japan, Korea, Australia - AR7598. Which kind of glue do I need to put those on M.2 card? Epoxy for developers, even though I don’t posses mandatory certificate? And all of this leads me to finding (for myself) that there might exist some similarities when selecting modem module for L5 or Linux-based TCU (telematics control unit), similar development challenges, not sure and just guessing, @Tatatirci don’t get me serious on this one. But still some hopes I might keep alive, if nobody objects with some arguments why Sierra Wireless AR modules cannot be an option if eventually put by experts on M.2 card.