mic input device not find

[Eamon.Yan]

When I download \nRFready Smart Remote 3 nRF52 v1.2.1alpha\nRF5x SDK-SR3\examples\ble_peripheral\smart_remote_3_nrf52\Projects\Firmware_nRF52832 to my 52832 device, I can't find the mic input device on my computer, either Windows or Linux. What's going on here

[Eamon.Yan]

Is it necessary to use p24 and p25? I use clk26,data25. Is that a problem?Buttons I have no use, my way is the Enable via bluetooth enabled audio data, but not the length of the audio data, a start to open the length of 38, transmission becomes 5 after dozens of length, the don't know why, I've tested, he the length of the data when I codec is set apcm has always been 131, but this state ubuntu can't identify the device.

[Øyvind]

CONFIG_IO_PDM_CLK and CONFIG_IO_PDM_DATA can be configured to match your HW. In Ubuntu 

CONFIG_AUDIO_HID_ENABLED should be set to 1. Both 

CONFIG_AUDIO_HID_ENABLED and CONFIG_AUDIO_ATVV_HID_ENABLED can be configured to 1, but ATVV  (Android TV Voice Service) needs an ADPCM audio codec configured to 8kHz and samples size of 256 bytes. 

If you choose Opus as an audio codec you can choose a variable or a set bit length. A variable bit length will cause a variable audio packet size. Also, the SR3 will fragment the audio packet with a size > MTU.

E.g. Opus with 40kbit/s data rate and 20ms frame length will produce a 102-byte audio packet every 20 ms (2-byte header added by us). If the MTU is 23, this 102-byte packet will be fragmented and sent as 5 x 20 byte + 1 x 2 byte. 

[Eamon.Yan]

My CONFIG_BLE_GATT_MAX_MTU_SIZE has been set to 247, which should not happen as you said