Oops, I accidentally replied to Mychaela directly, here's our conversation so far,
please others join in
with thoughts.
On Sun, Mar 10, 2019 at 09:09:31AM -0800, Mychaela Falconia wrote:
Hi Craig,
Thanks again for your details Mychaela. I will
read this very carefully
and keep it in mind as I try to port osmocom-bb to fernvale/mediatek.
I already expect a good dose of refactoring in layer1 so maybe I will touch
on fixing the issue.
Have you got yourself a CMU200 instrument or not yet? A CMU200 is
absolutely required if you wish to have any chance of success at your
idea of OBB on MTK.
I do have a Racal Instruments 6103E GSM Digital Radio Test Set which seems to
work well so far. I have tested some SIM800 modules (mtk6261) with the internal
BTS. Not sure if that will fall short or not but I'll take things one step at
a time. When I need a CMU200 I'll probably get one. :)
Another question: is there any way to run any official
MTK-based
firmware, however non-free and blob-laden it may be, on Fernvale hw?
Probably. I know from reading that Bunnie and Xobs who designed fernvale did
run standard firmware/OS on some similar 6260 based devices. Maybe we could
track down a good firmware and test on fernvale.
For what it's worth the fernvale isn't exactly my main target. I would much
rather
use a SIM800 module or eventually design of my own.
Has anyone actually done it and posted howto
instructions? If not,
then how do you know if the RF hw on your Fernvale kit is actually any
good and not physically defective? Whoever physically manufactured
those Fernvale boards sold by Sysmocom, have they actually tested
their RF hw and how? And what about calibration - have they performed
individual per-unit calibration of various RF parameters on those
Fernvale kits like every standard GSM MS hardware manufacturer is
required to?
I don't have any clue about these details. Will have to rely on Harald or
maybe inquire of Bunnie and Xobs.
I calibrate my FCDEV3B boards at production time, use
the calibration procedure to also serve as a test of the RF tract, and
ship every unit with turnkey-working official firmware and a fully
valid and legitimate IMEI, fully fit for operation as an MS on public
GSM networks - do they do likewise or not? If not, then they are
substandard.
M~
Thanks for your efforts,
Craig