TMS320F28379D: Question about interrupts: Are interrupts processed in series? Can they be processed in parallel on one CPU?

This topic has been discussed before on the forum. The links below should answer your question:  

https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/430318/will-a-tms320f28069-isr-interrupt-another-isr-of-lower-priority-while-the-lower-priority-isr-is-executing 

https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/491989/f28335-can-high-priority-interrupts-interrupt-low-priority-interrupts 

https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/930942/tms320f28069-why-does-the-low-priority-interrupts-get-pre-empted-if-the-isr-execution-time-of-the-higher-priority-interrupt-is-higher 

http://processors.wiki.ti.com/index.php/Interrupt_Nesting_on_C28x?cm_session=b04f8364-6ecb-4486-b6b3-7da02d3ccc9c&cm_type=link&cm_link=0477f331-371d-4bef-9df7-fcd3f124e495&utm_campaign=b04f8364-6ecb-4486-b6b3-7da02d3ccc9c&utm_medium=email&utm_source=contactmonkey&utm_content=sales%201%3a1&utm_term=RE%3a+Changing+interrupt+priority

Eric said:

Do all interrupts run in series? So, while one interrupt is running, no other interrupts can run until the interrupt has been acknowledged?

The 28x CPU can only execute one thread at a time, whether it is the main code or a ISR.

Eric said:

Or to get to a more core question, can only one interrupt be serviced at any one time? 

Yes, only one ISR can be serviced. However, if you are referring to nesting, the answer is in the links I have provided.

Eric said:

Or can interrupts be processed in parallel? If the interrupts are only processed in series, would you be able to switch between servicing two interrupts to give the effect of them running in parallel?

Please refer to the links above.