CC2564MODA: A2DP decoding period varies

Koichiro Tashiro

Part Number: CC2564MODA

Hi,

My customer is implementing A2DP with below HW+SW.
HW: DK-TM4C129X + CC2564MODA
SW: www.ti.com/.../CC256XM4BTBLESW

Customer changed the A2DP demo so that single SSI (SPI master mode) is used to send the data.
(LRCLK is generated from BCLK by on board circuit)
Customer found SSI suddenly stops sending data and debugging it now.
It seems CPU stops writing new data to SSI TX FIFO and it results in SSI stop.
(Please see “Data write” sheet in attached excel sheet)

Customer also checked the period of audio data decoding and found the decoding period shows strange behavior.
(Please see “Decoding” sheet in attached excel sheet)
Time used for decoding varies (from short time to longer time).
It seems SSI stops when the decoding time gets longer than certain threshold.
Why decoding period varies?
What is potential root cause of the issue?

A2DP_190930.xlsx

Thanks and regards,
Koichiro Tashiro

over 4 years ago

0 Vihang Parmar over 4 years ago

TI__Mastermind 29250 points

Hello Koichiro-san,

This question is more about the peripheral on the TM4C MCU and not about the Bluetooth stack. Assigning the thread to the relevant experts.

Best regards,

Vihang

0 Koichiro Tashiro over 4 years ago in reply to Vihang Parmar

TI__Mastermind 21140 points

Hi Vihang,

I am afraid the issue is nothing related to Tiva peripheral.
Customer reproduce the issue with A2DP demo without SSI operation (simply audio data are decoded, but not sent to SSI).

I guess the issue is inside SBC_Decode_Data() API.

Thanks and regards,
Koichiro Tashiro

0 Koichiro Tashiro over 4 years ago in reply to Koichiro Tashiro

TI__Mastermind 21140 points

As there are some misunderstandings in the device behaviors, this thread is closed.

I submitted new thread.

https://e2e.ti.com/support/wireless-connectivity/bluetooth/f/538/t/846755

Thanks and regards,
Koichiro Tashiro

Bluetooth®︎

Bluetooth forum

CC2564MODA: A2DP decoding period varies