Sharing TSM30 source

[Michael Sokolov]

Ben Thompson <ben.thompson at yandex.ru> wrote:

> Here is my attempt :-
> http://wiki.openmoko.org/wiki/Image:Gta02a6_comms_chips_under_shield.JPG

This photo is pretty good - thanks!  From it we can tell that:

* The RF transceiver chip is TRF6151C, just like the one on the
  Leonardo board for which we have the docs.  It's a *quad-band* GSM
  RF transceiver chip, although it isn't obvious from the pinout: it
  has 3 differential-pair RF inputs, but one of them (the one called
  GSM in the datasheet) handles both 900 and 850 MHz Rx.  (1800 MHz Rx
  is on the DCS input pair and 1900 MHz Rx is on the PCS one.)  The RF
  outputs going to the PA are single-ended and combined: one for the
  low bands, one for the high bands.

* The RF PA (power amplifier) is the classic RF3166, once again the
  same as what one would find in a "vanilla" Calypso phone.  The
  Leonardo board schematics feature AWT6108, but also say: "Second
  source option is RF3133 from RF Micro Devices that can be used on
  same footprint".

* The shiny block component (corresponding to U401 in Om's "component
  placement" PDF doc) must be the antenna switch.  One can also see 3
  little components next to it, corresponding to U402 through U404.  I
  reason that these must be the SAW filters for the 3 bands supported
  by each GTA02 version.  It's too bad that Om-Inc chose not to use a
  part like M034F instead (an antenna switch version with the SAW
  filters built in), as that would have made it a quad-band phone: all
  other components are already quad-band-ready.

I wonder if the only difference between the 850/1800/1900 MHz and
900/1800/1900 MHz versions of the GTA02 is in that one SAW filter part
that sits between the low-band output pins of the antenna switch and
the low-band input pins of the TRF6151C.  (What makes me think so?
See how real quad-band phones based on the same Calypso chipset handle
it: Leonardo_plus_quadband_schem.pdf and the M034F.pdf in my PDF
Calypso doc collection.)

Makes me wonder if a GTA02 can be changed from one version to the
other by carefully replacing that one part and changing the Calypso FW
image accordingly...

Now we need to figure out what the RF block looks like in the TSM30:
that would tell us whether or not the RF chip control code is something
we would need to be concerned with when porting the TSM30 source to
the GTA02.  What we *really* need are TSM30 schematics.  Schematics
used to be included in phone service manuals, but I don't know how to
search for a service manual in Spanish...

MS