--- a/doc/C155-target	Wed Nov 07 06:55:49 2018 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,64 +0,0 @@
-In the early years of FreeCalypso, when we made our first attempt at FC GSM
-firmware that was eventually retired under the name Citrine, we supported
-running that fw on the Mot C155/156 target in addition to the other two C1xx
-subfamilies.  However, that C155 target support in not available in our current
-Magnetite and Selenite firmwares.  We are not doing any work to support that
-target in our current fw because it does not provide anything of value that is
-not better provided by other targets:
-
-* If your goal is to have a practically usable phone, the simpler C139/140 is a
-  better choice than C155/156: C155 uses a ringtone generator chip for which no
-  docs could be found, thus we may not be able to make it ring (in contrast,
-  C139 uses a piezoelectric buzzer driven by the Calypso itself), and C155's
-  LCD controller is much less obvious than the one in the C139 - the latter
-  already works the way we like.
-
-* If instead you would like a platform for playing with non-UI modem firmware
-  (which is all that our previous Citrine fw provided), then the only platform
-  which we officially support and endorse for that purpose is our own FCDEV3B.
-  It is not reasonable at this point to ask us to expend unpaid volunteer time
-  to support a hardware platform that is not made or sold by us when instead
-  you should be supporting our work by buying the hardware which we do make.
-
-If you wish to strike out on your own and try to resurrect C155 target support
-in FC Selenite or Magnetite, your first difficulty will be that you won't be
-able to run our fw entirely out of RAM without flashing like we did when running
-Citrine on this target.  FC Citrine implemented an FFS-in-RAM hack as an
-alternative to using a real FFS in flash, but this hack is not present in
-Magnetite or Selenite, thus unless you go even further out and resurrect that
-hack as well, you will have to flash your firmware.  If you take the route of
-flashing your fw, you will have to decide between one of two possible
-approaches:
-
-Approach 1: you can keep this target's original bootloader that expects the
-main fw image to begin at 0x20000 with a hand-off interface that is new to the
-C155 (different from the more basic C1xx subfamilies), and build your fw to fit
-this C155 boot interface.  This approach was supported in Citrine (although not
-actually used because it was much easier to run via fc-xram w/o flashing) and
-can be easily resurrected in the gcc build of Selenite.  However, it would be a
-lot more difficult to get this approach to work with TI's original TMS470
-environment: doing so would require major surgery on their assembly code and
-linker script magic, which I am not comfortable with because we have no docs or
-sources for those assembler and linker tools.  You will also face the same
-problem if you resurrect our old FFS-in-RAM hack and try to build a fw image
-that runs entirely out of RAM w/o flashing: it is easy to do in the gcc
-environment, but not in TMS470.
-
-Approach 2: you can replace the bootloader with the one we use on the more
-basic C1xx phones (compal-flash-boot-for-fc.bin), in which case you will have
-complications with loadtools (the ARM vs. Thumb entry point difference for
-serially loaded code), but you can work around that issue by running fc-loadtool
-and fc-xram with -h c155 -c plain instead of just -h c155 after you change the
-bootloader, or you can create yet another patched bootloader version that does
-the Thumb entry point for serially loaded code like C155 original but hands off
-to the main fw in flash in the older C1xx fashion.  Either way you will then be
-able to build flashable fw images for this boot-modified C155 in the same manner
-as how we do it for the more basic C1xx targets, and thus have both TMS470 and
-gcc environments.
-
-As you can see from the above, it will be messy and unpleasant no matter which
-way you lick it, and we (FreeCalypso Central) are not going to do this work for
-free, whereas doing it on a commercial consulting basis would cost a lot more
-than the $500 USD retail price of our own FreeCalypso development board
-(FCDEV3B) that avoids all of these problems and is a much nicer platform for
-Calypso sw/fw development.