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annotate compal/audio/omr-guide @ 379:a760a5eeed65

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compal/audio/omr-guide: another avenue of investigation
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 10 Oct 2021 19:53:35 +0000
parents
children
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a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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1 When a C139 phone is booted up with a headset jack serial cable already
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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2 inserted, it behaves in an interesting manner: if you *don't* perform the
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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3 **16379# step, rvinterf running on the host won't see any output from the phone
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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4 beyond a little bit on boot, but if you send an omr command through fc-tmsh,
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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5 you get a response! The same behaviour occurs if you first boot the phone
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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6 normally with nothing in the headset jack, then insert the serial cable. It
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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7 looks like the electrical switch inside the phone is still set to connect the
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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8 headset jack to the UART, but the firmware suppresses its continuous trace
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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9 output beyond TM responses.
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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10
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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11 Using this omr method, I was able to read the same DSP API words which we have
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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12 previously read via tfc139 break-in method; the bytes read via omr out of DSP
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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13 API memory locations corresponding to FIR coefficients and AEC config match what
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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14 we got via tfc139 break-in followed by fc-loadtool peeking.
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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15
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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16 Now comes the next ambitious part: we know that oabbr is broken in Compal's fw
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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17 and thus can't be used to read ABB registers, but at least in TI's reference fw
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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18 the writes to Iota VBC registers are done via the DSP, rather than via the MCU
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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19 to ABB interface. Does Compal's fw do likewise? Can we read out DSP API words
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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20 through which these VBC registers are written? Let's give it a try! We need
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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21 to begin by calculating the absolute addresses which we will need to read via
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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22 omr:
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
23
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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24 DSP NDB start address is 0xFFD001A8
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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25
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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26 d_vbctrl1 addr: 0xFFD001A8 + 0x44 = 0xFFD001EC
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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27 d_vbctrl2 addr: 0xFFD001A8 + 0x2E = 0xFFD001D6
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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28 d_vbuctrl addr: 0xFFD001A8 + 0x34 = 0xFFD001DC
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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29 d_vbdctrl addr: 0xFFD001A8 + 0x36 = 0xFFD001DE
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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30
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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31 Result: the bytes read out via omr do match what we got earlier by breaking in
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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32 with tfc139 and reading the ABB registers via abbr in fc-loadtool! This
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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33 observation gives us hope: if we do build the special hardware hack for
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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34 connecting to UART signal contact pads without going through the headset jack,
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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35 then there is a good chance that we will be able to use omr to read out the
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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36 firmware's audio settings for the handheld mode. Furthermore, if we don't
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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37 trigger the switch into headset mode and if we don't kill the fw with tfc139,
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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38 then we may be able to do omr readouts while the fw is running with a SIM,
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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39 connected to a GSM network, and making a call - a confidence boost for the
a760a5eeed65 compal/audio/omr-guide: another avenue of investigation
Mychaela Falconia <falcon@freecalypso.org>
parents:
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40 audio settings, plus we may be able to figure out how volume control works.