DAC AD1862: Almost THT, I2S input, NOS, R-2R

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In the meantime :cool:
 
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@miro1360 I really appreciate the efforts you are putting in to help DIY community making different variations of excellent DACs which are better than many commercial products.

I recently noticed another addition to the project which is CPLD based logic to replace the shift registers. Although I have never played with Altera or Xilinx devices before but having a general idea I was thinking wouldn't it be possible to develop signal switching (I2S 2-3 in 1 out or emulation of shift registers and then out to the DAC chips), with the hope that EPM240 has enough juice and memory to do it.

Just an idea..

Have ordered a few boards though.
Do you mean the switcher implemented directly in the I2S to PCM CPLD (2 functions in 1 CPLD? 😁) ... it is possible, but it needs a lot of testing and coding :geek:

The easiest way is to use this inputs selector as separate device :unsure: #2909
 
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Do you mean the switcher implemented directly in the I2S to PCM CPLD (2 functions in 1 CPLD? 😁) ... it is possible, but it needs a lot of testing and coding :geek:

The easiest way is to use this inputs selector as separate device :unsure: #2909
yes that's what i was thinking (aloud) may be add a visual interface. Well that will depend how fast I could learn/implement VHDL I guess. I think its more efficient this way. While I was doing some surfing I did come across a gentleman who had implemented the core of PCM2706 in CPLD as college project.
Lets see.

About post#2909 I already have the boards with my, populated all of them now I have a few extra. I am keeping only 2 of them.
 
@rehanabid
I implemented that switch into the 20-bit project, untested, you can test it.
Connect button on pin 3 and GND (pin 3 will be shorted to the GND with this button).
There is not implemented debouncer in code. I tried to avoid it by configuring the input as schmitt trigger (maybe it does not work that way and switching inputs will be chaotic - if so, try to add a small capacitor (47nF?) on pin 3 and GND as a passive button debouncer).
Maybe it won't work at all 😁
 

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@rehanabid
I implemented that switch into the 20-bit project, untested, you can test it.
Connect button on pin 3 and GND (pin 3 will be shorted to the GND with this button).
There is not implemented debouncer in code. I tried to avoid it by configuring the input as schmitt trigger (maybe it does not work that way and switching inputs will be chaotic - if so, try to add a small capacitor (47nF?) on pin 3 and GND as a passive button debouncer).
Maybe it won't work at all

Thanks @miro1360 just waiting for my boards to arrive, which are currently stuck in customs. With eid holidays and all that hopefully receive them somewhere next week, after that I will start experimenting with them.

Hopefully will come-up with something, should i succeed will share it here.

miro highly appreciate you willingness to share, efforts of your hard work with the DIY community.
 
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Now I figured out, that you asked for "3 I2S inputs to 1 PCM output" and I created the opposite (1 I2S input to 3 PCM outputs) :rofl:
Here is the correct version "3 I2S inputs to 1 20-bit PCM output" :cool:
thanks miro will experiment with the code once I receive the cpld boards. once successfully tested will share with rest of the board.
 
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