04-26-2023, 01:57 PM
Sorry for any confusion.
Inside the enclosure, I use a short USB cable between the Pi and the Tone Board. This cable also provides power. The board *is not* a DAC HAT for the Pi nor did I attempt to wire up the I2S pins.
As it happens, the Vim edition of the board comes with a 40-pin connector that appears to physically fit the Pi GPIO pins but that’s irrelevant. Even if the signal levels and pin-out were compatible, there’s no Khadas I2S driver available for the Pi. Apart from the presence of that connector, the two editions are identical and both can be used as a USB DAC. (Actually, the board I have is the Vim edition. I just removed the 40-pin connector because it was taking up space.)
Used as a USB DAC, the Khadas Tone Board needs no vendor-specific driver, as Al has already explained. The onboard microcontroller handles the standard USB communications.
Two notes: the board has an S/PDIF input but I don’t use it. The board can play DSD streams in addition to regular PCM streams but the board’s hardware volume control works only for PCM streams. I have no DSD material so this doesn’t matter to me. (PCM streams come from MP3, FLAC, etc., tracks.)
Regards,
Kent
Inside the enclosure, I use a short USB cable between the Pi and the Tone Board. This cable also provides power. The board *is not* a DAC HAT for the Pi nor did I attempt to wire up the I2S pins.
As it happens, the Vim edition of the board comes with a 40-pin connector that appears to physically fit the Pi GPIO pins but that’s irrelevant. Even if the signal levels and pin-out were compatible, there’s no Khadas I2S driver available for the Pi. Apart from the presence of that connector, the two editions are identical and both can be used as a USB DAC. (Actually, the board I have is the Vim edition. I just removed the 40-pin connector because it was taking up space.)
Used as a USB DAC, the Khadas Tone Board needs no vendor-specific driver, as Al has already explained. The onboard microcontroller handles the standard USB communications.
Two notes: the board has an S/PDIF input but I don’t use it. The board can play DSD streams in addition to regular PCM streams but the board’s hardware volume control works only for PCM streams. I have no DSD material so this doesn’t matter to me. (PCM streams come from MP3, FLAC, etc., tracks.)
Regards,
Kent
