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−Modem configurations
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−====================
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−
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−If you would like to build our Magnetite firmware for the Standard Modem
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−functionality (voice, SMS, CSD, fax and GPRS services enabled, control via AT
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−commands, no UI, two UARTs are expected to be available for the AT command
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−interface and for the RVTMUX binary packet interface), you have 3 specific
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−configurations to choose from, differing in the level of deblobbing:
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−
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−classic		This configuration replicates classic TCS211, just like
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−		leo2moko from 2013.  Almost all of the original binary blob
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−		libraries are used; the only components that are recompiled
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−		from source are those which we got in source form with our copy
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−		of TCS211 from Sotovik.  This config can only be built for the
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−		fcdev3b and gtamodem targets, not any others.
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−
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−l1reconst	In this configuration the Layer1 component of the firmware
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−		(which came as a blob in our copy of TCS211) is recompiled from
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−		reconstructed source, and the same is done for the system
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−		initialization code in main.lib.  The entire chipsetsw division
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−		of the firmware (now in src/cs) is thus recompiled from source,
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−		either original or reconstructed, and the only components that
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−		are used as blobs are the G23M PS, GPF and Nucleus.  This
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−		config can be built for all targets.
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−
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−hybrid		This configuration is a TCS2/TCS3 hybrid.  Instead of using the
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−		TCS211 version of the G23M protocol stack which we got only as
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−		binary blobs, this config uses the G23M PS version from the
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−		TCS3.2/LoCosto source, backported to work with L1 and the fw
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−		foundation layers from TCS211.  ACI also had to be replaced with
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−		the TCS3 version, and a special hybrid version of the cdginc
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−		headers had to be constructed.  L1 and the init code are also
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−		deblobbed as in l1reconst.  Like l1reconst, this config can be
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−		built for all targets, and it is currently the most deblobbed
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−		(closest to full source) Magnetite config: the only remaining
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−		blobs are GPF and Nucleus.
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−
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−All 3 of the above configurations have CSD, fax and GPRS enabled; this
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−functionality can only be exercised on those hardware targets on which both
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−Calypso UARTs are brought out, with the MODEM UART presenting a standard ASCII
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−AT command interface including data functions, while the IrDA UART carries the
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−RVTMUX interface for debug trace and other development functions.  If you are
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−interacting with your Calypso target modem or pseudo-modem solely through
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−RVTMUX, without access to the ASCII AT command interface on the dedicated MODEM
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−UART, then the data functions of the firmware are inaccessible and act as dead
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−weight.
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−
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−Having fully deblobbed all of L1, we now have the ability to build our hybrid
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−firmware not only for the Standard Modem functionality with all data services
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−enabled as above, but also in a stripped-down "voice pseudo-modem"
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−configuration - see the Voice-pseudo-modem article.
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−
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−The deblobbing of L1 has been done in a very meticulous manner, ensuring that
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−each individual reconstructed C module compiles into a strict functional
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−equivalent of the original binary blob, sometimes even matching bit for bit -
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−thus no regressions are expected with the classic->l1reconst transition, and no
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−extensive testing is deemed necessary beyond the basic tests that have already
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−been done.  However, the transition from l1reconst to hybrid involves wholesale
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−replacement of two major firmware components (G23M PS and ACI) and some
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−important associated support pieces with entirely different versions from a
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−different TI program, hence it can certainly benefit from more thorough testing.
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−
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−So far the most-deblobbed hybrid config looks very promising: voice, SMS and
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−GPRS work perfectly in my (Mother Mychaela's) lab environment, and even CSD has
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−finally been proven to work as well on 2018-06-21.  CSD functionality has been
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−extremely difficult to test because it has been very unreliable lately on the
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−network side in my geographical location (T-Mobile USA), with CSD calls failing
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−something like 99.9% of the time with a NO CARRIER response to the ATD command,
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−using exactly the same modem hardware and firmware that worked flawlessly for
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−CSD several years earlier, which makes it extremely difficult to test CSD calls
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−with new firmware - but I finally succeeded in making a CSD call from an FCDEV3B
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−running FC Magnetite hybrid on 2018-06-21, proving that the new hybrid fw is
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−good for CSD functionality in addition to the better-tested voice, SMS and GPRS.