Greg-R

Very helpful—thank you so much!

There is finite isolation between the lineout and the headphone. My application is a radio transceiver. In CW mode (Morse code), there is a very strong audio tone sent out on both left and right line out. With the headphone muted using the...

Might be old world but I use "and" and "or". I do use ! instead of "not", but ! does not confuse me, or lead to easy errors which are damnably difficult to find.

"Extremely hard to reproduce" and "conservative approach that prevents those problems". That's what I was looking for, the specific justification for disabling/enabling interrupts. So the interrupt disables are now well understood and will stay...

Removing the interrupt disables was a quick test to see if it would fail. Next, I am going to reduce the CPU frequency in steps to see if I can make it fail, and if it does fail, then add the interrupt disables back in to see if that fixes the...

Code protected inside a __disable_irq()/__enable_irq() bracket is called a critical section - datastructures shared with an ISR must be handled with critical sections, its quite simple. Then the ISR and the critical sections get serialized...

So you need to block the isr() which is run by the DMA in the middle and at the end of the data buffer. Thank you for the description of the audio system interrupt scheme! That is very helpful. I'm trying to think of some way of diagramming or...

Teensy has priority nested interrupts. Audio uses 2 of the priority levels. Those update() functions run from a low priority interrupt, which is the reason the audio library can process audio automatically while other code and Arduino libraries...

I'm working on a 4-output I2S class for the Open Audio Library. I'm trying to find the reason why code in the update() method of the 2-output I2S is done with interrupts disabled in some parts of the code. Here is an example from the 2-output...