Disabling IRQ for better performance - Teensy 4.1

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roni.fli

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We'r sampling two pins (A,B Encoder) at frequency upto 10mhz.
When the code was simple read/count the readings matched the input pulse.
once we extended the project , added Ethernet communication with PC & Debug printing to Serial
we began to see inconsistent readings.
At the code that does the reading & calculation
i disabled those interrupt: (tried also putting priority to 255 , didn't help)
NVIC_DISABLE_IRQ(IRQ_USB1);
NVIC_DISABLE_IRQ(IRQ_ENET);
NVIC_DISABLE_IRQ(IRQ_PIT);
And reenabled them once the counting ended.
And performance is back on track , But from this moment
no response from Serial Or Ethernet
How do i "Revive" back the Irq for those ?

Our project is quite simple , replacing encoder counters with the Teensy on our machines
The test is also simple , pulse generator on the input pin ,
counting for 1000msec , and expecting to get the same result on each trial
 
MarkT said:
You know the T4 has hardware quadrature decoders built in and there's a library to use them?
https://forum.pjrc.com/threads/58478-Teensy-4-x-H-W-Quadrature-Encoder-Library
Click to expand...

Unfortunately it's not good for us since it's slow (relative)
using an Interrupt as the encoder source is slower then poling IO
we use Linear Encoder (0.1u) at a rate of 600mm/sec (6mhz) at a range of 600mm !
using IO poling i manage to keep up with the rate , but as an example:
Tic -> 0.25usec , every 20 ticks i send a Peg (set IO) so every 5usec a peg is sent
during this session (3000msec) i get one peg which lasts 52usec ,
after disabling
NVIC_DISABLE_IRQ(IRQ_USB1),NVIC_DISABLE_IRQ(IRQ_ENET),NVIC_DISABLE_IRQ(IRQ_PIT);
all the pegs comes out correctly.
But then i reenable the IRQ , but my network & Serial are not working anymore !
so my problem is how to "Revive" back those IRQ
 
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