I'm trying to develop a multi-canal system with ADAU1452 in TDM16 mode that communicates to ADAU1966A in Standalone Mode (TDM16, Slave serial audio interface and 256 × Fs ). I control the DSP with SigmaStudio. The system is able to convert the digital data from the DSP, but when I tried to send a signal, in this example a sinusoidal signal with a frequency of 800Hz, what I saw with the oscilloscope is represented in the figure 1. The sinusoidal signals of the two channels are truncated in the same time intervals and this reproduces an audible artifacts.
(fig.1 - two output signals from DAC in TDM16 Mode)
The EVAL-ADAU1452RevBZ sends to ADAU1966A: GND (black wire), BCLK (red long wire), LRCLK (blue wire) and DSDATA (yellow long wire) (fig.2). The board with ADAU1966A has been designed following the specifications described in the datasheet and its clock is generated by the internal crytal oscillator.
(fig.2 connection between EVAL-ADAU1452RevBZ and the board with ADAU1966A)
The configuration of the serial output port in Sigmastudio is:
- LRCLK is master with type Pulse and Positive polarity
- BCLK is master with Negative polarity
- Word lenght 24 bits
- MSB position = I2S - BCLK delay by 1
- TDM mode = 16 channels, 32 bit/channel
- Clock generator = Clock generator 1 (48 kHz (FS) generator)
- Sampling rate = Fs (48kHz)
How can this problem be solved? I think that it's a problem of PLL and different master clock, is it possible?
Sorry for my bad english and
I tried to configure the entire system in TDM8 pulse too and, with the same sinusoidal signal of 800 Hz, the outputs are always truncated but with a certain of periodicity (fig. 3)(fig.1 - two output signals from DAC in TDM8 Mode)