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May 26, 2026 at 10:29 am #2457

draven_ts
Participant

    1)
    if i DON’T cycle the discoverable state, when I try send the following command ‘OPEN … AGHFP’, the source device will show ‘PENDING’ on the UART but hang forever (despite the other paired module on and in range)…

    The Command manual for IOT777 suggests that when sending the ‘OPEN’ cmd the device should be in (Pairing mode). I’ve noticed on startup the module boots up into (pairing mode) as noticed by the UART message ‘PAIR_PENDING’. However, if the device is paired, then loses connection, it seems it will no longer be in (pairing mode).

    In this case, instead of power cycling the module to put it back into pairing mode, i’ve noticed that by cycling the discoverable state, after sending ‘DISCOVERABLE ON’, i receive the message on the UART ‘PAIR_PENDING’ which puts it back into pairing mode and therefore will allow the ‘OPEN … AGHFP’ cmd to work.

    2)
    I don’t believe it to be a timing issue given that i’m able to reproduce the issue fairly quickly using the procedure i’ve documented. but also unable to reproduce the issue using the exact same procedure aside from ending the call before power cycling. Also, the UART responses for the good and bad case look exactly the same. The only functional difference being the fact there is no actual audio coming out of the headset device.

    I’ll attach annotated pictures of both UART logs for headset and source devices for both Good and bad test cases. Note, these logs begin after both modules are connected and activly streaming audio in HFP and the power is pulled from the headset. (the beginning of my step 1).

    For the GOOD case:

    image

    For the Failed case:

    image

    You’ll notice there is no difference in the UART to indicate the audio is not working. If i issue ‘STATUS’ in both the good and bad test cases I receive the same response :

    For Source:
    STATE CONNECTABLE[ON] DISCOVERABLE[ON] ADVERTISING[ON] SCAN_UNI[OFF]
    LINK 12 CONNECTED AGHFP 245DFC0201AD ACTIVE WB

    For Headset:
    STATE CONNECTABLE[ON] DISCOVERABLE[IDLE] ADVERTISING[ON] SCAN_UNI[OFF]
    LINK 13 CONNECTED HFP 245DFC03B624 ACTIVE WB