FreeCalypso > hg > fc-magnetite

comparison doc/Leonardo-target @ 678:edaceb78719a

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
doc/Leonardo-target: Tango unused Calypso signals update
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 20 Jun 2020 05:08:39 +0000
parents 6edd9be81b94
children
comparison
equal deleted inserted replaced
677:91d9f8506420 678:edaceb78719a
120 Magnetite-Leonardo fw build target is really just a reference for practically 120 Magnetite-Leonardo fw build target is really just a reference for practically
121 non-existent hw, and given the unknown of what other Leonardo variants may have 121 non-existent hw, and given the unknown of what other Leonardo variants may have
122 existed once beyond our known schematics, we would rather leave a few floating 122 existed once beyond our known schematics, we would rather leave a few floating
123 inputs than risk causing a driver conflict on some unknown board. 123 inputs than risk causing a driver conflict on some unknown board.
124 124
125 In the case of Tango these 3 just-mentioned Calypso signals are contained inside 125 In the case of Tango these 3 just-mentioned Calypso signals (as well as
126 the module (not brought out), and it is currently unknown if they are simply 126 BCLKX/GPIO6) have been confirmed to be unconnected at their Calypso ball pads
127 unconnected or if perhaps they are tied to either GND or V-IO inside the module. 127 (not brought out externally, not used internally for anything, not tied or
128 The Tango manuf's original fw leaves these signals in their power-up default as 128 pulled to either GND or V-IO), thus we configure them as dummy outputs,
129 Calypso inputs, hence we do the same currently in order to not risk causing a 129 eliminating floating inputs.
130 short. At some later time when our finances allow doing so, we may send a
131 sacrificial Tango module for destructive PCB reverse eng and see what is really
132 done with these Calypso signals - if they are really unconnected, then we can
133 change the code to switch them to outputs, just like we have done for the
134 gtamodem target where the original manuf's official fw also left a bunch of
135 floating inputs.