Video of my REcon talk and other FreeCalypso news

Mychaela Falconia mychaela.falconia at gmail.com
Tue Dec 5 07:17:19 UTC 2017


Hello FreeCalypso community,

The REcon people have just posted the second batch of video recordings
from this past summer's conference, and my presentation is among them:

https://recon.cx/2017/montreal/recordings/

In other news, I am working on implementing battery charging in FC
Magnetite firmware.  TI already had not one but two incarnations of
the battery charging driver for the Calypso+Iota chipset platform: the
first version called PWR and the second version called LCC, both in
the form of RiViera SWEs - but neither of them works the way we need,
hence I am writing a new one of my own, also in the form of a RiViera
SWE.

TI's LCC stands for "low-cost charger", and this charging driver is
written to run on hardware that takes "low-cost" unregulated chargers,
i.e., charging adapters that put out rectified AC without any
regulation, with the voltage flying between 0 and crazy high (TI's
docs say 20 V) on every AC mains cycle.  Needless to say, none of the
phones we target in FreeCalypso (neither Mot C1xx nor the Pirelli
DP-L10 nor my desired semi-clone of the latter) use such crazy
unregulated chargers, instead all of our target phones use regulated
5 VDC charging power sources, USB or otherwise.  Hence TI's LCC code
is totally inappropriate for our hardware targets.

TI's older PWR code did target the much simpler charging hardware
architecture like what our C1xx and Pirelli targets use, and the debug
trace output from Pirelli's fw makes it very clear that they had
resurrected this older PWR battery management code.  However, when I
tried to do likewise in FreeCalypso, I quickly learned that this PWR
code (as we got it from the MV100 source fragments) is so broken that
at least in our circumstances (the circumstances under which Pirelli's
fw authors operated were certainly different), it makes more sense to
just write an entirely new (third!) version of the battery charging
driver than to rework the original PWR SWE into something sensible.

The new battery charging driver I am writing is called FCHG
(FreeCalypso charging), and I expect it to work on both Mot C139 and
Pirelli DP-L10 targets - and if we ever build our own FreeCalypso
handset hardware, it will work the same there as well.

In yet other news, TechnoTronix folks had promised to me earlier that
toward the end of this week (December 7 or 8) they will have my
experimental FCDEV3B RoHS boards assembled - this experimental board
build is the first in a series of experiments seeking to shed light on
the sleep mode bug mystery, and it is a mystery which we need to solve
before we can consider producing FCDEV3B boards in a significantly
larger batch quantity to bring the per-unit price down, and before we
can start the next board design based on the FCDEV3B.

Hasta la Victoria, Siempre,
Mychaela aka The Mother


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