Linux/TMS320DM8148: MCASP2 AUD_CLKIN0 PLL

mike A

Tool/software: Linux

Hi,

I am working on the audio codec which doesn’t have a output clock, I want set the macps2 clk input to AUD_CLKIN0, can a unused pll be used to generate 44.1/48Khz to AUD_CLKIN0 ?

44.1/48Khz

something like OSC 20Mhz-->> Unused pll ---->> AUD_CLKIN0----->>mcasp2

Thank And Regards,

Mike

over 8 years ago

0 Pavel Botev over 8 years ago

TI__Guru**** 170625 points

Hi Mike,

When pin L5 is used in AUD_CLKIN0 mode, this pin can be input only. See DM814x datasheet, sections
3.2.18 Oscillator/PLL, Audio Reference Clocks, and Clock Generator
7.4.3 AUD_CLKINx Input Clocks
7.4.5 External Input Clocks

Thus AUD_CLKIN0 signal should be sourced from external clock generator, not from DM814x PLL.

Regards,
Pavel

0 mike A over 8 years ago in reply to Pavel Botev

Genius 3490 points

Hi Pavel,

Thanks for the clarification, I had a look the audio clk can also have source from ATL atclk can this be used from a dm8148 pll.

Thanks And Regards,
Mike

0 Pavel Botev over 8 years ago in reply to mike A

TI__Guru**** 170625 points

Mike,

ATL module is not documented in DM814x datasheet, thus it is not available for DM814x device. Note that TRM is generic, while datasheet is specific for the device and with highest priority.

Regards,
Pavel

Processors

Processors forum

Linux/TMS320DM8148: MCASP2 AUD_CLKIN0 PLL