Guide to 768k PCM
Posted: Wed Dec 01, 2021 1:51 pm
Hello,
is there any official or known to work manual how to achieve 768k PCM USB audio ?
I found couple of unanswered or old topics like:
https://www.xcore.com/viewtopic.php?f=2 ... 68k#p38900
https://www.xcore.com/viewtopic.php?f=2 ... 68k#p36830
https://www.xcore.com/viewtopic.php?f=37&t=8193
Based on informations i found, there are only few things to change in reference project:
#define MCLK_441 (1024*44100) /* 44.1, 88.2 etc */
#define MCLK_48 (1024*48000) /* 48, 96 etc */
#define MAX_FREQ (768000)
And here is my main question:
Do I need external ~45 MHz and ~49 MHz oscillators ?
Can this be achieved on ~22 MHz and ~24 MHz default ones ?
On standard clocks, my audio is being played, but its quite noisy.
Any help would be very nice !
Best
is there any official or known to work manual how to achieve 768k PCM USB audio ?
I found couple of unanswered or old topics like:
https://www.xcore.com/viewtopic.php?f=2 ... 68k#p38900
https://www.xcore.com/viewtopic.php?f=2 ... 68k#p36830
https://www.xcore.com/viewtopic.php?f=37&t=8193
Based on informations i found, there are only few things to change in reference project:
#define MCLK_441 (1024*44100) /* 44.1, 88.2 etc */
#define MCLK_48 (1024*48000) /* 48, 96 etc */
#define MAX_FREQ (768000)
And here is my main question:
Do I need external ~45 MHz and ~49 MHz oscillators ?
Can this be achieved on ~22 MHz and ~24 MHz default ones ?
On standard clocks, my audio is being played, but its quite noisy.
Any help would be very nice !
Best