External DAC

[tllim]

Hi....as per my knowledge the first RPis had no I2S, but the RPi 1 PCB Rev. 2.0 added the P5 header which has I2S CLK/FSYNC/DIN/DOUT as alternate function on GPIOs 28-31. RPI B+ and RPI 2 moved this signals to the extended 40 pin header (previously 26 pins).Unfortunately the Pine has I2S on the euler bus, not on the RPI header, thus it is not fully pin compatible.The Pine has the I2S master clock signal which is required by some I2S DACs.The pine also has the S/PDIF compatible OWA (one wire audio) which directly connects to an optical transceiver

On the I2S signal prospective, Pine64 and RPi are not compatible. We prefer the digital audio has its own well define section, instead of piggy back on GPIO pin.