ESP32 - engine.init() Core selection not working!?

[j0k3r187]

Hello, first of all, thanks for this Library. Im trying to run this library with a Async Webserver but after starting the Server the Steppermotor is stuttering a lot. Like its not getting precise Step signals. Im using an ESP32-WROOM 32, but testet on different ESP32 DevkitC V4 Modules with the same result.

I thought if i use Arduino Core: 0, Event Core: 0 and engine.init(1) then my Stepper is running on Core 1 and the Webserver on Core 0. But no matter what combination of Arduino Core, Event Core and engine.init() the Stepper keeps stuttering.

Here is an example to repoduce this:

Testrun 1 is running without any problem. After starting a simple Server Testrun 2 is Stuttering.

Testprogramm

#include "Arduino.h" #include "WiFi.h" #include "AsyncTCP.h" #include "ESPAsyncWebServer.h" #include "FastAccelStepper.h" ///// Netzwerk Parameter const char *AP_ssid = "ESP32_MotorControl"; const char *AP_password = "ADMIN123"; const char *http_username = "w"; const char *http_password = "w"; IPAddress local_IP(192, 168, 0, 187); IPAddress gateway(192, 168, 0, 1); IPAddress subnet(255, 255, 0, 0); IPAddress AP_subnet(255, 255, 255, 0); IPAddress primaryDNS(8, 8, 8, 8); // optional IPAddress secondaryDNS(8, 8, 4, 4); // optional AsyncWebServer server(80); ///// Pin´s int EN_PIN = 4; int STEP_PIN = 16; int DIR_PIN = 5; FastAccelStepperEngine engine = FastAccelStepperEngine(); FastAccelStepper *stepper = NULL; void setup() { Serial.begin(115200); engine.init(); stepper = engine.stepperConnectToPin(STEP_PIN); if (stepper) { stepper->setDirectionPin(DIR_PIN); stepper->setEnablePin(EN_PIN, false); // (Enable Pin, LOW Active) stepper->setAutoEnable(false); stepper->enableOutputs(); stepper->setSpeedInUs(300); stepper->setAcceleration(10000); } Serial.println("Start Testrun 1 . . ."); stepper->runForward(); delay(2000); stepper->forceStop(); ///// Server Setup if (!WiFi.softAPConfig(local_IP, gateway, AP_subnet)) { Serial.println("WiFi AP Config failed!"); } // Start in AP Mode Serial.println("Starting in AP Mode!"); if (!WiFi.softAP(AP_ssid, AP_password)) { Serial.println("WiFi AP Mode failed!"); return; } else { Serial.println(WiFi.softAPIP()); } // Start server server.begin(); Serial.println("Start Testrun 2 . . ."); stepper->runForward(); delay(2000); stepper->forceStop(); } void loop(){ delay(1); }

ps. The delay(1); is needed if Arduino Core runs on Core 0, otherwise ESP keeps Rebooting

[gin66]

seems related issues: The WiFi task suspends other tasks on both cores of ESP32 ESP32 hardware ISR sometimes not triggered when wifi is transmitting

The preconditions for FastAccelStepper to run smoothly are IMHO:

• no suspension/blocking of the stepper task
• no other interrupts blocking the cpu for longer than the fastest time step
• no writes to the flash e.g. OTA/writing, because the stepper task code is in flash. writes <4ms may be ok.

No idea, how to make the WiFi driver more cooperative.

Another user has used bluetooth successfully with FastAccelStepper, if the Wifi issue cannot be resolved.

[gin66]

FreeRTOS is a cooperative OS, so a loop() without task switch will block the core. If arduino core is running on core 0, then the watchdog will not be serviced anymore and will trigger a watchdog reset. AFAIK on core 1, there is no watchdog.

Instead of delay() you can use taskYIELD().

[gin66]

stale