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−TI's TCS211 firmware for the Calypso+Iota+Rita chipset maintains a number of
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−tables for RF calibration and configuration.  These tables can be saved in the
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−non-volatile flash file system (FFS), as normally required for per-unit RF
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−calibration; tables that are saved in FFS will be automatically read when the
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−firmware boots and whenever it switches between 900+1800 and 850+1900 MHz band
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−pairs.  There is also a compiled-in default for each of the tables built into
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−the firmware image; these defaults are used whenever a given table is not found
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−in FFS.
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−
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−The firmware also provides Test Mode commands (accessed via the RVTMUX binary
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−packet interface) through which an external host can read and write the in-RAM
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−working copies of these RF calibration and configuration tables; the standard
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−expected workflow is as follows:
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−
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−* When the firmware first boots on a freshly manufactured board with a blank
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−  FFS, the in-RAM working tables are loaded from the compiled-in defaults.
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−
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−* The factory production test and RF calibration station connects to the
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−  running firmware via RVTMUX, and as it goes through the requisite calibration
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−  steps, properly adjusted RF tables are formed in the firmware's working in-RAM
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−  locations.
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−
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−* The production test and calibration station sends some special command packets
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−  (encoded via the MISC_ENABLE opcode) to the firmware; these commands tell the
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−  firmware to take the in-RAM RF tables and save them in the non-volatile FFS.
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−  There are separate me commands for saving different groups of RF tables,
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−  divided into RF calibration, RF config, Tx calibration, Tx config,
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−  Rx calibration and Rx config.  The tables in the Tx config and Rx config
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−  groups are never modified in practice, hence they are usually not written
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−  into FFS and the fw uses the compiled-in versions instead.
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−
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−* In normal operation the GSM device firmware reads the RF calibration and
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−  configuration tables that have been written into FFS on the production line
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−  and subsequently persist for the lifetime of the device.
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−
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−FreeCalypso tools provide the following support for working with these tables:
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−
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−* We have defined our own ASCII text-based format in which each of the RF tables
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−  implemented by TCS211 fw can be represented.  This text format is both human-
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−  and machine-readable.
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−
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−* Our fc-tmsh utility (the tool that exchanges Test Mode command packets with
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−  running firmwares) supports rftw and rftr commands for reading and writing
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−  the fw's in-RAM RF tables via RF_TABLE_WRITE and RF_TABLE_READ command
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−  packets.  Our implementation of the rftw command takes the table data input
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−  in the form of ASCII text files in our format, and the tables read back from
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−  the fw via the rftr command can be written out into host files in the same
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−  format with the save-rf-table command.
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−
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−* RF tables that have been saved in the non-volatile FFS can be read out
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−  "in vivo" via fc-fsio or "in vitro" from a raw flash dump via tiffs.  They
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−  are in the firmware's native binary format.  Our fc-cal2text utility can be
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−  used to convert these binary files into our adopted text format for easier
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−  analysis.  The conversion is lossless.
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−
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−* Any RF table in our ASCII format can be converted back into the corresponding
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−  native binary with our fc-cal2bin utility.
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−
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−* Each RF table type for which there is a directly corresponding file in FFS
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−  can be uploaded into the FFS of a FreeCalypso GSM device directly from our
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−  ASCII format with the fc-fsio utility's upload-rf-table command.
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−
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−In the case of two particular RF tables there is a slight difference between
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−the way they are stored in FFS and the way they are read and written via Test
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−Mode commands:
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−
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−* The firmware maintains 3 separate tables for il2agc (input level to AGC)
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−  conversion, to be used in different circumstances.  As it happens, the
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−  compiled-in default is the same for all 3 tables and these tables are never
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−  changed in practice, but "by the book" they are still 3 separate tables.
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−  In FFS all 3 tables are concatenated together in a single file
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−  /gsm/rf/rx/il2agc, but for the rftw and rftr command packet exchanges they
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−  are 3 separate tables.
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−
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−* For each supported frequency band there is a table of Tx power ramp-up and
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−  ramp-down profiles.  Each single ramp is 16 bytes, each ramp-up & ramp-down
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−  pair is 32 bytes, and the firmware allows for 16 of these stored templates.
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−  The complete table is stored in FFS as a single file of 512 bytes, but it is
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−  too big for the TM3 protocol.  Instead the Test Mode protocol provides
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−  dedicated TX_TEMPLATE_WRITE (ttw) and TX_TEMPLATE_READ (ttr) commands which
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−  write or read one 32-byte template at a time.
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−
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−Our FreeCalypso ASCII RF table format includes support for a table of type
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−tx-ramps; these ramps tables can be written by fc-cal2text, converted back to
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−native binary with fc-cal2bin and uploaded with fc-fsio's upload-rf-table
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−command, but cannot be uploaded with fc-tmsh's rftw command corresponding to
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−the RF_TABLE_WRITE Test Mode command.  There is also an ASCII format for a
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−single Tx ramp template that can be uploaded with the ttw command; templates
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−read back via the ttr command can be saved in the same format with the
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−save-tx-ramp command.
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−
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−In the case of the il2agc table, a FreeCalypso ASCII RF table of type il2agc is
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−singular as in the Test Mode protocol, not triple as in FFS.