Hi
Need a simple circuit (hopefully DIY) to allow the digital output of a CD to input into an Arduino digital IO pin.
Any help appreciated.
Best regards.

 

Hi
Need a simple circuit (hopefully DIY) to allow the digital output of a CD to input into an Arduino digital IO pin.
Any help appreciated.
Best regards.

Could you explain what you are trying to do? What is the problem you are trying to solve this way?

On the surface, your request doesn’t really make sense. More information is needed to help you, and why you want to do this will fill in a lot of it.

 

Thanks for your reply Ya'akov.
The intent is to convert the serial digital data from the cd output to parallel data, using software.
There are several hardware ways (D flip flops, shift registers), but I choose software.

What is the problem you are trying to solve this way?

The problem is I need a circuit (preferably DIY) to interface with the Arduino.
Can you offer a circuit that can fix this problem.
Best regards.

 

Is this a school project?

 

Is this a school project?

No.
I'm 77 and have a desire to learn, but not to go back to school.
The purpose of this "little project" is to convert serial data into parallel data.
Before it gets to the DAC I can reassign the output pin arrangements in software.
This will produce interesting sounds , most will sound like the Sex Pistols , but occasionally there will be a little nugget.
Thats where the fun starts for me.
Record, cut and splice etc.
Back to the original quest.
I hope to get the serial digital bit stream to talk to the Arduino digital IO pin.
Any help with this circuit is appreciated.
Best regards.
PS: just had a thought. If I played a Sex Pistols cd, it may sound all right.

 

No.
I'm 77 and have a desire to learn, but not to go back to school.
The purpose of this "little project" is to convert serial data into parallel data.
Before it gets to the DAC I can reassign the output pin arrangements in software.
This will produce interesting sounds , most will sound like the Sex Pistols , but occasionally there will be a little nugget.
Thats where the fun starts for me.
Record, cut and splice etc.
Back to the original quest.
I hope to get the serial digital bit stream to talk to the Arduino digital IO pin.
Any help with this circuit is appreciated.
Best regards.
PS: just had a thought. If I played a Sex Pistols cd, it may sound all right.

Just so I have this straight:

Your plan to interface the optical fiber output from a CD player to an unspecified “Arduino“ development board via a GPIO pin.

Then you are going to decode the S/PDIF protocol, grab the audio samples, process them into discrete levels, shuffle the bits in some way intended to modify the resulting sound, shift them onto a set of other GPIO pins, and use that to interface a DAC to make analog recordings of the result.

This would mean you need a fiber optic receiver with an appropriate connector, like this one on AliExpress. I don’t see a datasheet for it, but the pinout suggests it is a very simple device. I suspect it is as simple as VCC determines VOUT but throwing it on a scope with a signal from the CD player should clear things up.

I would start at 3V3 in case the part is low voltage and switch to 5V if 3V3 doesn’t seem to work.

I have serious doubts that an “Arduino” with code written against the Arduino libraries is going to have the compute power to decode S/PDIF, jigger the samples, then load them out a set of pins in real time.

I am also not clear how you intend to manipulate the bits in a way that will produce anything but (not very clever) distortion.

This is a hobby project so however I’d seriously consider just doing the whole thing inside a more capable computer by ripping a CD to a .wav file, playing with the bits, and writing a new .wav file to disk. At the very least you will be able to see if your expected manipulations create anything interesting before spending your time on hardware that adds a layer of complexity to something that might not have and salutary effect on the resulting sound.

In any case, good luck—and welcome to AAC. I hope you will be making yourself a regular here, there are a lot of really good people both in terms of knowledge and of personal qualities.

 

Just so I have this straight:

Your plan to interface the optical fiber output from a CD player to an unspecified “Arduino“ development board via a GPIO pin.

Then you are going to decode the S/PDIF protocol, grab the audio samples, process them into discrete levels, shuffle the bits in some way intended to modify the resulting sound, shift them onto a set of other GPIO pins, and use that to interface a DAC to make analog recordings of the result.

This would mean you need a fiber optic receiver with an appropriate connector, like this one on AliExpress. I don’t see a datasheet for it, but the pinout suggests it is a very simple device. I suspect it is as simple as VCC determines VOUT but throwing it on a scope with a signal from the CD player should clear things up.

I would start at 3V3 in case the part is low voltage and switch to 5V if 3V3 doesn’t seem to work.

I have serious doubts that an “Arduino” with code written against the Arduino libraries is going to have the compute power to decode S/PDIF, jigger the samples, then load them out a set of pins in real time.

I am also not clear how you intend to manipulate the bits in a way that will produce anything but (not very clever) distortion.

This is a hobby project so however I’d seriously consider just doing the whole thing inside a more capable computer by ripping a CD to a .wav file, playing with the bits, and writing a new .wav file to disk. At the very least you will be able to see if your expected manipulations create anything interesting before spending your time on hardware that adds a layer of complexity to something that might not have and salutary effect on the resulting sound.

In any case, good luck—and welcome to AAC. I hope you will be making yourself a regular here, there are a lot of really good people both in terms of knowledge and of personal qualities.

The board is an Arduino Mega 2560

I am also not clear how you intend to manipulate the bits in a way that will produce anything but (not very clever) distortion.

In the code I plan to use Arrays to rearrange the output order from MSB to LSB, in this case pins 22 to 37.

Thanks for your tips.
Best regards.