Search found 36 matches

by HelWeb
Sat Dec 21, 2019 5:56 am
Forum: ESP-IDF
Topic: [Question]: Maximum interrupt rate on GPIO
Replies: 6
Views: 17795

Re: [Question]: Maximum interrupt rate on GPIO

Dear Mr. jgustavoam, I do not get your results - and they are impossible. Your display of channel 2 is wrong - I tested it with my scope. With the PWM-frequency at pin 2 and connected to the interrupt pin 4 the following will happen: Interrupt routine 5 is called. The total time from external interr...
by HelWeb
Sat Dec 21, 2019 4:57 am
Forum: ESP-IDF
Topic: [Question]: Maximum interrupt rate on GPIO
Replies: 6
Views: 17795

Re: [Question]: Maximum interrupt rate on GPIO

My measurements show: 1.7 µs from external interrupt to interrupt routine => about 500000 Interrupts/s.
If you are willing to dedicate core 1 only for "interrupts" you can work with more than 3.000.000 interrupts per second.
Look at
https://github.com/MacLeod-D/ESp32-Fast-external-IRQs
by HelWeb
Sat Dec 21, 2019 4:08 am
Forum: General Discussion
Topic: High frequency GPIO Interrupt
Replies: 4
Views: 8018

Re: High frequency GPIO Interrupt

My measurements:
From external interrupt to interrupt routine; 1.7 µs
From external interrupt to RTOS task via interrupt routine like you do: 7.6 µs

So there should be no problem.

May you want to look at:
https://github.com/MacLeod-D/ESp32-Fast-external-IRQs
by HelWeb
Sat Dec 21, 2019 3:23 am
Forum: ESP-IDF
Topic: Reduce external interrupt latency
Replies: 15
Views: 26692

Re: Reduce external interrupt latency

The ESP32 has 2 cores and for most applications one core running RTOS-tasks is enough. If we dedicate the 2. core to a single - never interrupted - task we can achieve - while running a WebServer ! - count and react on more than 3,000,000 external "interrupts" per second - building pulses with a gra...
by HelWeb
Thu Dec 12, 2019 2:46 am
Forum: ESP-IDF
Topic: Reduce external interrupt latency
Replies: 15
Views: 26692

Re: Reduce external interrupt latency

@edigi32
You are right!
As I mentioned: "this workaround may help."
It is an act of despair. But the prices of ESP32 are so low ;)
Maybe for some of us it is a solution.
:D
by HelWeb
Sat Aug 10, 2019 8:20 pm
Forum: General Discussion
Topic: ADC calibration with VREF
Replies: 5
Views: 28632

Re: ADC calibration with VREF

Maybe you may want to test: esp32.com/viewtopic.php?f=19&t=2881&start=30 Posted: Sat Aug 10, 2019 12:30 pm You may calibrate your own ESP32( the nonlinear 11DB curve) with this program.<br> All you need is a wire from pin 25 to pin 35 and a normal voltmeter.<br> Calibration is done automatically.<br...
by HelWeb
Sat Aug 10, 2019 8:11 pm
Forum: General Discussion
Topic: ADC Calibrated Value still not correct?
Replies: 4
Views: 10452

Re: ADC Calibrated Value still not correct?

Maybe you may want to test: esp32.com/viewtopic.php?f=19&t=2881&start=30 Posted: Sat Aug 10, 2019 12:30 pm You may calibrate your own ESP32( the nonlinear 11DB curve) with this program.<br> All you need is a wire from pin 25 to pin 35 and a normal voltmeter.<br> Calibration is done automatically.<br...
by HelWeb
Sat Aug 10, 2019 8:06 pm
Forum: Hardware
Topic: ESP32 ADC Calibration curves?
Replies: 18
Views: 35118

Re: ESP32 ADC Calibration curves?

Maybe you may want to test: esp32.com/viewtopic.php?f=19&t=2881&start=30 Posted: Sat Aug 10, 2019 12:30 pm You may calibrate your own ESP32( the nonlinear 11DB curve) with this program.<br> All you need is a wire from pin 25 to pin 35 and a normal voltmeter.<br> Calibration is done automatically.<br...
by HelWeb
Sat Aug 10, 2019 10:30 am
Forum: ESP32 Arduino
Topic: ESP32 ADC Non-linear Issues - How do I fix / change Attenuation or width?
Replies: 43
Views: 127656

Re: ESP32 ADC Non-linear Issues - How do I fix / change Attenuation or width?

Is it possible to get precise results from ESP32-ADC ? As told we need a LUT for that. I could not resist to do it myself as a proof of concept :D AND FOR ME IT WORKS VERY WELL. This time I estimate the ESP32-DAC produces correct values. ====================== NOTE ==================================...
by HelWeb
Fri Aug 09, 2019 7:54 pm
Forum: ESP32 Arduino
Topic: ESP32 ADC Non-linear Issues - How do I fix / change Attenuation or width?
Replies: 43
Views: 127656

Re: ESP32 ADC Non-linear Issues - How do I fix / change Attenuation or width?

Original_Output.jpg ( for the images 10 bit values are used: DA>>2, AD<<2) I got same strange results like vseven in his first post. I wanted to put DA voltage (8bit) to pin 25 (DAC_CHANNEL_1) and then (pin 25 connected to pin 35) read back the voltage with adcStart(35),adcEnd(35); shifted from 12 ...