PIN Problems interfacing Audio Codec & BT Audio to BBB (MCASP)

Hello,

i’m having some trouble building a new custom cape for BBB which has audio codec (TLV320AIC3104) and bluetooth audio (CC2564MODA) - maybe someone that is experienced in MCASP can help?

First of all, the only solution i see is to use MCASP0 for AUDIO and MCASP1 for BLUETOOTH AUDIO. I don’t think you can connect both chips to MCASP0?

When wiring up the ICs, i run into a serious PIN collision conflict:

TLV320AIC3104 | | | |

  • | - | - | - |

Codec PIN | BBB PIN | BBB PIN Name | Signal |
MCLK | P9_25 | GPIO3_21 | mcasp0_ahclkx |
BCLK | P9_31 | SPI1_SCLK | mcasp0_aclkx |
WCLK | P9_29 | SPI1_D0 | mcasp0_fsx |
DIN | P9_28 | SPI1_CS0 | mcasp0_axr2 |
DOUT | P9_30 | SPI1_D1 | mcasp0_axr0 |

CC2564MODA | | | |

Codec PIN | BBB PIN | BBB PIN Name | Signal |
BCLK | P9_42B | GPIO3_18 | mcasp1_aclkx |
WCLK | P9_27 | GPIO3_19 | mcasp1_fsx |
DIN | P9_41B | GPIO3_20 | mcasp1_axr0 |
DOUT | P9_25 | GPIO3_21 | mcasp1_axr1 |

Unfortunately using another mcasp1_axr instead of axr1 is impossible (MII block most PINs), also muxing mcasp0_ahclkx to another PIN is impossible because of my design (LCD PINs block this way).

In some audio cape schematics, MCLK of TLV320AIC3104 is not even connected to BBB header but is connected directly to 12MHz Oscillator.

My question is, do i really have to connect MCLK ↔ mcasp0_ahclkx to make TLV320 work on BBB or can i use 12MHz Oscillator ↔ MCLK instead? Which way is better? What might have to be changed in software if using ext. Oscillator?

Thank you very much!!
Chris