--- a/doc/Calypso-version-override	Mon Oct 07 03:59:14 2019 +0000
+++ b/doc/Calypso-version-override	Mon Nov 18 05:03:15 2019 +0000
@@ -1,11 +1,12 @@
 TI's TCS211 program supported 3 different Calypso silicon versions on their
 D-Sample and Leonardo boards: C05B (CHIPSET 8, DSP 33), early C035 (CHIPSET 10,
 DSP 34) and final C035 (CHIPSET 10, DSP 36).  In FreeCalypso we generally work
-only with the last chipset (final C035), but we would like to support the two
-earlier ones as well, if possible.  C05B has been partially exercised on the
-Mother's D-Sample board (non-functional Clara RF, no genuine tpudrv10.c source
-and too many unknowns), but the early C035 version with DSP 34 has not been
-tested at all yet.
+only with the last chipset (final C035), but we also support the two earlier
+ones to a good extent.  C05B has been partially exercised on the Mother's
+D-Sample board (non-functional Clara RF, no genuine tpudrv10.c source and too
+many unknowns, but at least some of the DSP-based audio services work), whereas
+Calypso C035 with DSP 34 has been tested and found to work on a specially
+modified FCDEV3B board - see the FCDEV3B-751774 article.
 
 All 3 Calypso chip versions in question are footprint-compatible, i.e., they
 can all be populated onto the same PCB.  Changing between C05 and C035 requires
@@ -17,8 +18,8 @@
 C035 on the same PCB; the schematics we have for Leonardo show fixed VLRTC
 strapping for C035, but there also existed an earlier Leonardo version with
 Calypso C05B.  Our own FCDEV3B also has fixed C035-only VLRTC strapping, our
-regular boards have final C035 chips on them, but we should be able to build
-some experimental boards with an early C035 variant (751774) for DSP 34 testing.
+regular boards have final C035 chips on them, but we have put a D751774AGHH
+chip on one experimental board for DSP 34 testing.
 
 In the case of target boards that can have different Calypso chip versions
 populated on them, we want to be able to target all of them without creating a

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/doc/FCDEV3B-751774	Mon Nov 18 05:03:15 2019 +0000
@@ -0,0 +1,29 @@
+We have one experimental FCDEV3B V2 board on which our regular Calypso chip
+([P]D751992AGHH) has been replaced with D751774AGHH, an earlier F-number
+featuring DSP ROM version 3416 rather than the final version 3606 which we
+normally work with.  Both chip versions are Calypso C035 variants (ARM7 running
+at 52 MHz, DSP running at 104 MHz), and both include AMR support - but there
+must have been some issue with DSP version 34 (and maybe version 35 used in
+Calypso+) that compelled TI to produce the newer and final version 36 which we
+are most familiar with.
+
+Our Layer1 code is based on TI's TCS211-20070608 semi-src release (which we have
+reconstructed back to full source), and it officially supports only DSP 36.
+However, our FC Magnetite firmware can also be built for DSP 34 targets (see
+the Calypso-version-override article), in which case we use a monolithic DSP
+patch (no L1_DYN_DSP_DWNLD) extracted from the TSM30 source.  The patch version
+is 4130.
+
+The configure.sh target name for this special modified board is fcdev3b-dsp34
+instead of just fcdev3b, and the two firmware builds are not interchangeable:
+the regular fcdev3b build goes into regular FCDEV3B boards, the special
+fcdev3b-dsp34 build goes into the special FCDEV3B-751774 board.  However, when
+running its respective build this DSP 34 board appears to function just as well
+as our regular DSP 36 targets: standalone RF tests work, DSP-based audio
+services (beeps and Melody E1) work, connecting to a live GSM network worked,
+a few test voice calls worked, all of them connected in AMR mode, voice passed
+successfully in both directions.
+
+Going forward, we shall continue using D751992AGHH chips with DSP ROM version
+3606 as our regular platform, but it is nice to know that the earlier DSP 34
+apparently works too.