On Wed, Mar 16, 2005 at 07:01:51PM +0200, Per Mellander wrote:
On Wed, 16 Mar 2005 13:39:44 +0100, Roland Praml wrote
Long time ago there were so called 'copy-bit killer' Can I set the nonaudio with a similar circuit.
Yes you can, it's a similar control bit. It was in an Elektor magazine a few years ago. Maybe you can modify the circuit. It was all done in hardware because of the high rate.
As other mentioned this should also be done by a soundcard by reading from spdif-in, set the bit, and writing to spdif-out
I was thinking the same but it seems that a dsPIC is the only ( reasonable ) uController that can work in that high speed area. ( Unless the soundcard is equipped with such a feature. )
The speed rate is
32 bit word per 16 bit PCM sample multiplied with 2 for two channels multiplied with 2 for the biphase-mark-code multiplied with e.g. 48kHz
which is 6.144MHz
... now you have to read the preamble of each 32 bit word to catch the starting one and rise the status bit of the second and third (aka second bit for the second channel) status bit and maybe the parity bit is needed. And this should be switchable by the DVB driver or firmware via a not used pin of the ARM.
Werner