Hey
I am designing a system that has a 5x2 I2S switching chip. I want to be able to take the audio signal (I2S) from BOTH outputs of the switch, bring them into an Audio Codec, mix them with another analog signal (line/mic level) and then output the new I2S data.
I was looking at the PCM3070 -
There is a primary and secondary I2S interface. The primary interface has dedicated pins for clocking(BCLK and WCLK), Dout and Din.
The secondary interface uses pins MFP3 and MFP4 for serial data in and out respectively. Obviously I will lose the primary function of those pins(SPI bus)
Table 2-2 in the PCM3070 reference guide shows the register settings to set the pins correctly
However if you look at fig 2.43 the Din and S_DIN are muxed before they go into the “Audio Digital Serial Interface” – I assume this is the “Data interface” in fig 1.1 – i.e. only one stream at a time? I don’t see how you can control this mux, even if we can control that mux I'm not sure how we can take two serial I2S streams at the same time.
If I can't use this device to take two I2S streams in simultaneous is theer another option?
Cheers
Calum