How can external clock be used in hardware mode?
I would use the more traditional combination (22.576Mhz / 24.576Mhz) in hardware mode, but generally the implementations are in software mode.
I did not want to have to include microcontrollers. How can this be possible in conjunction with the CS8416 / DIR9001 .. etc .. with CS4398/PCM1794A?
I would use the more traditional combination (22.576Mhz / 24.576Mhz) in hardware mode, but generally the implementations are in software mode.
I did not want to have to include microcontrollers. How can this be possible in conjunction with the CS8416 / DIR9001 .. etc .. with CS4398/PCM1794A?
Please read the datasheet of CS, I think that You will find settings for slave mode with ehternal MCK input. 8414 have this option. To use receiver with external MCK, not PLL recovered from the SPDIF. Probably DIR receiver have the same option?
But there is a problem: how to achieve automatic choosing of 2 clock rates...
1. You can use one CS in master mode with pins indication which clock is present then ENable indicated external to the 2nd CS receiver slave mode.
2. use some device for determining what MCK base is on then ENable...
3. manual switch by reading sampling rate from the song data.
...
external MCK units should be the first one in the power ON chain - turn power on MCKs first.
Maybe the MCK should be divided, Because it is 2X rated from max SR of the receivers.
BUT that walues are good for optional Reckloking digital bus out from the receiver.
cheers
But there is a problem: how to achieve automatic choosing of 2 clock rates...
1. You can use one CS in master mode with pins indication which clock is present then ENable indicated external to the 2nd CS receiver slave mode.
2. use some device for determining what MCK base is on then ENable...
3. manual switch by reading sampling rate from the song data.
...
external MCK units should be the first one in the power ON chain - turn power on MCKs first.
Maybe the MCK should be divided, Because it is 2X rated from max SR of the receivers.
BUT that walues are good for optional Reckloking digital bus out from the receiver.
cheers
I have read the datasheet from CS8416, but I have not found the explanation about this. What I found was in relation to the OMCK pin, but it is something around 12Mhz.
I do not mind having to manually select with a switch according to the sample rate. Ex: 44.1khz 88.2khz / 48khz 96khz. (Actually, that's exactly what I want)
If that's possible.
I'll continue studying.
Best Regards.
I do not mind having to manually select with a switch according to the sample rate. Ex: 44.1khz 88.2khz / 48khz 96khz. (Actually, that's exactly what I want)
If that's possible.
I'll continue studying.
Best Regards.
If I understood your questions correctly...
As far as I know, CS8416 as many SPDIF receivers use external MCLK only for determining the sample rate so that you can read it from the register, or for outputting some clock when PLL is unlocked. When you have incoming SPDIF signal and PLL is locked onto that, the clocks going forward are then provided by the PPL. These devices work without MCLK/crystal altogether.
Think of it like that, if you have your crystals onboard and SPDIF signal coming in, the sample rate of incoming signal and divided MCLK will never be exactly the same. I think the only way to overcome that is a long buffer. This two-crystal idea works if your device provides clocks for the source, e.g. USB interface.
As far as I know, CS8416 as many SPDIF receivers use external MCLK only for determining the sample rate so that you can read it from the register, or for outputting some clock when PLL is unlocked. When you have incoming SPDIF signal and PLL is locked onto that, the clocks going forward are then provided by the PPL. These devices work without MCLK/crystal altogether.
Think of it like that, if you have your crystals onboard and SPDIF signal coming in, the sample rate of incoming signal and divided MCLK will never be exactly the same. I think the only way to overcome that is a long buffer. This two-crystal idea works if your device provides clocks for the source, e.g. USB interface.
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