I would like to send digital audio data from the ADAU1761 to an external device, where the ADAU1761 acts as master. The wanted format is 48 kHz stereo I2S with two 16 bits samples (left+right) per frame. LRCLK should be 50% duty cycle. This means in total 32 BCLK cycles per frame.
According to the ADAU1761 Rev C datasheet table 25, it should support 32-64 BCLK cycles per audio frame, referring to the BPF field in the Serial Port Control 1 register (0x4016). But in the description of the BPF field, there are only options for 48, 64, 128 and 256 BCLK cycles per frame, 32 BCLK cycles per frame is not listed.
I can successfully configure the port and get output data other rates, for example 64 BCLK cycles per frame. So the port itself works, but I fail to configure it to 32 BCLK cycles per frame.
Did I misunderstand some information or is it not possible to configure the serial port for the format we are targeting?