Hello,
My project goal is to create a wireless way of transmitting a throttle value (variable resistor) to another device that will translate that value into a PWM signal, which will eventually go into a different device that we can black-box. I have purchased 2x ESP32-C3 devices that have wireless capabilities. These are Tourdeus brand, and it looks like they're not reputable, so maybe that's what's causing my strife.
I have a video below explaining my issue, but in short, I am seeing good, predictable behavior as I bring the "throttle" from 0-50%-ish. However, after that, it seems like I'm not getting a good readout from the "throttle". To add to my troubleshooting woes, I can't figure out for the life of me how to debug this, as I get no output on the COM line I connect to. I'm just at a loss.
https://www.youtube.com/watch?v=1G-eTuHRVjE
If you have any ideas or an easier way to accomplish this project, please let me know.
/**
ESPNOW - Basic communication - Slave
Date: 26th September 2017
Author: Arvind Ravulavaru <https://github.com/arvindr21>
Purpose: ESPNow Communication between a Master ESP32 and a Slave ESP32
Description: This sketch consists of the code for the Slave module.
Resources: (A bit outdated)
a. https://espressif.com/sites/default/files/documentation/esp-now_user_guide_en.pdf
b. http://www.esploradores.com/practica-6-conexion-esp-now/
<< This Device Slave >>
Flow: Master
Step 1 : ESPNow Init on Master and set it in STA mode
Step 2 : Start scanning for Slave ESP32 (we have added a prefix of `slave` to the SSID of slave for an easy setup)
Step 3 : Once found, add Slave as peer
Step 4 : Register for send callback
Step 5 : Start Transmitting data from Master to Slave
Flow: Slave
Step 1 : ESPNow Init on Slave
Step 2 : Update the SSID of Slave with a prefix of `slave`
Step 3 : Set Slave in AP mode
Step 4 : Register for receive callback and wait for data
Step 5 : Once data arrives, print it in the serial monitor
Note: Master and Slave have been defined to easily understand the setup.
Based on the ESPNOW API, there is no concept of Master and Slave.
Any devices can act as master or salve.
*/
#include <esp_now.h>
#include <WiFi.h>
#define CHANNEL 1
// Init ESP Now with fallback
void InitESPNow() {
WiFi.disconnect();
if (esp_now_init() == ESP_OK) {
Serial.println("ESPNow Init Success");
}
else {
Serial.println("ESPNow Init Failed");
// Retry InitESPNow, add a counte and then restart?
// InitESPNow();
// or Simply Restart
ESP.restart();
}
}
// config AP SSID
void configDeviceAP() {
const char *SSID = "Slave_1";
bool result = WiFi.softAP(SSID, "Slave_1_Password", CHANNEL, 0);
if (!result) {
Serial.println("AP Config failed.");
} else {
Serial.println("AP Config Success. Broadcasting with AP: " + String(SSID));
Serial.print("AP CHANNEL "); Serial.println(WiFi.channel());
}
}
void setup() {
Serial.begin(115200);
Serial.println("ESPNow/Basic/Slave Example");
//Set device in AP mode to begin with
WiFi.mode(WIFI_AP);
// configure device AP mode
configDeviceAP();
// This is the mac address of the Slave in AP Mode
Serial.print("AP MAC: "); Serial.println(WiFi.softAPmacAddress());
// Init ESPNow with a fallback logic
InitESPNow();
// Once ESPNow is successfully Init, we will register for recv CB to
// get recv packer info.
esp_now_register_recv_cb(OnDataRecv);
pinMode(LED_BUILTIN, OUTPUT);
pinMode(0, OUTPUT);
pinMode(1, OUTPUT);
pinMode(2, OUTPUT);
}
// callback when data is recv from Master
void OnDataRecv(const uint8_t *mac_addr, const uint8_t *data, int data_len) {
char macStr[18];
snprintf(macStr, sizeof(macStr), "%02x:%02x:%02x:%02x:%02x:%02x",
mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);
Serial.print("Last Packet Recv from: "); Serial.println(macStr);
Serial.print("Last Packet Recv Data: "); Serial.println(*data);
Serial.println("");
modulateBrightness(*data);
if (*data > 32) {
digitalWrite(0, HIGH);
} else {
digitalWrite(0, LOW);
}
if (*data > 64) {
digitalWrite(1, HIGH);
} else {
digitalWrite(1, LOW);
}
if (*data > 128) {
digitalWrite(2, HIGH);
} else {
digitalWrite(2, LOW);
}
}
void modulateBrightness(uint8_t brightness) {
digitalWrite(LED_BUILTIN, HIGH);
delay(brightness);
digitalWrite(LED_BUILTIN, LOW);
delay(500-brightness);
}
void loop() {
// Chill
}
/**
ESPNOW - Basic communication - Master
Date: 26th September 2017
Author: Arvind Ravulavaru <https://github.com/arvindr21>
Purpose: ESPNow Communication between a Master ESP32 and a Slave ESP32
Description: This sketch consists of the code for the Master module.
Resources: (A bit outdated)
a. https://espressif.com/sites/default/files/documentation/esp-now_user_guide_en.pdf
b. http://www.esploradores.com/practica-6-conexion-esp-now/
<< This Device Master >>
Flow: Master
Step 1 : ESPNow Init on Master and set it in STA mode
Step 2 : Start scanning for Slave ESP32 (we have added a prefix of `slave` to the SSID of slave for an easy setup)
Step 3 : Once found, add Slave as peer
Step 4 : Register for send callback
Step 5 : Start Transmitting data from Master to Slave
Flow: Slave
Step 1 : ESPNow Init on Slave
Step 2 : Update the SSID of Slave with a prefix of `slave`
Step 3 : Set Slave in AP mode
Step 4 : Register for receive callback and wait for data
Step 5 : Once data arrives, print it in the serial monitor
Note: Master and Slave have been defined to easily understand the setup.
Based on the ESPNOW API, there is no concept of Master and Slave.
Any devices can act as master or salve.
*/
#include <esp_now.h>
#include <WiFi.h>
#include <esp_wifi.h> // only for esp_wifi_set_channel()
// Global copy of slave
esp_now_peer_info_t slave;
#define CHANNEL 1
#define PRINTSCANRESULTS 0
#define DELETEBEFOREPAIR 0
// Init ESP Now with fallback
void InitESPNow() {
WiFi.disconnect();
if (esp_now_init() == ESP_OK) {
Serial.println("ESPNow Init Success");
}
else {
Serial.println("ESPNow Init Failed");
// Retry InitESPNow, add a counte and then restart?
// InitESPNow();
// or Simply Restart
ESP.restart();
}
}
// Scan for slaves in AP mode
void ScanForSlave() {
int16_t scanResults = WiFi.scanNetworks(false, false, false, 300, CHANNEL); // Scan only on one channel
// reset on each scan
bool slaveFound = 0;
memset(&slave, 0, sizeof(slave));
Serial.println("");
if (scanResults == 0) {
Serial.println("No WiFi devices in AP Mode found");
} else {
Serial.print("Found "); Serial.print(scanResults); Serial.println(" devices ");
for (int i = 0; i < scanResults; ++i) {
// Print SSID and RSSI for each device found
String SSID = WiFi.SSID(i);
int32_t RSSI = WiFi.RSSI(i);
String BSSIDstr = WiFi.BSSIDstr(i);
if (PRINTSCANRESULTS) {
Serial.print(i + 1);
Serial.print(": ");
Serial.print(SSID);
Serial.print(" (");
Serial.print(RSSI);
Serial.print(")");
Serial.println("");
}
delay(10);
// Check if the current device starts with `Slave`
if (SSID.indexOf("Slave") == 0) {
// SSID of interest
Serial.println("Found a Slave.");
Serial.print(i + 1); Serial.print(": "); Serial.print(SSID); Serial.print(" ["); Serial.print(BSSIDstr); Serial.print("]"); Serial.print(" ("); Serial.print(RSSI); Serial.print(")"); Serial.println("");
// Get BSSID => Mac Address of the Slave
int mac[6];
if ( 6 == sscanf(BSSIDstr.c_str(), "%x:%x:%x:%x:%x:%x", &mac[0], &mac[1], &mac[2], &mac[3], &mac[4], &mac[5] ) ) {
for (int ii = 0; ii < 6; ++ii ) {
slave.peer_addr[ii] = (uint8_t) mac[ii];
}
}
slave.channel = CHANNEL; // pick a channel
slave.encrypt = 0; // no encryption
slaveFound = 1;
// we are planning to have only one slave in this example;
// Hence, break after we find one, to be a bit efficient
break;
}
}
}
if (slaveFound) {
Serial.println("Slave Found, processing..");
} else {
Serial.println("Slave Not Found, trying again.");
}
// clean up ram
WiFi.scanDelete();
}
// Check if the slave is already paired with the master.
// If not, pair the slave with master
bool manageSlave() {
if (slave.channel == CHANNEL) {
if (DELETEBEFOREPAIR) {
deletePeer();
}
Serial.print("Slave Status: ");
// check if the peer exists
bool exists = esp_now_is_peer_exist(slave.peer_addr);
if ( exists) {
// Slave already paired.
digitalWrite(LED_BUILTIN, HIGH);
Serial.println("Already Paired");
return true;
} else {
// Slave not paired, attempt pair
digitalWrite(LED_BUILTIN, LOW);
esp_err_t addStatus = esp_now_add_peer(&slave);
if (addStatus == ESP_OK) {
// Pair success
Serial.println("Pair success");
return true;
} else if (addStatus == ESP_ERR_ESPNOW_NOT_INIT) {
// How did we get so far!!
Serial.println("ESPNOW Not Init");
return false;
} else if (addStatus == ESP_ERR_ESPNOW_ARG) {
Serial.println("Invalid Argument");
return false;
} else if (addStatus == ESP_ERR_ESPNOW_FULL) {
Serial.println("Peer list full");
return false;
} else if (addStatus == ESP_ERR_ESPNOW_NO_MEM) {
Serial.println("Out of memory");
return false;
} else if (addStatus == ESP_ERR_ESPNOW_EXIST) {
Serial.println("Peer Exists");
return true;
} else {
Serial.println("Not sure what happened");
return false;
}
}
} else {
// No slave found to process
Serial.println("No Slave found to process");
return false;
}
}
void deletePeer() {
esp_err_t delStatus = esp_now_del_peer(slave.peer_addr);
Serial.print("Slave Delete Status: ");
if (delStatus == ESP_OK) {
// Delete success
Serial.println("Success");
} else if (delStatus == ESP_ERR_ESPNOW_NOT_INIT) {
// How did we get so far!!
Serial.println("ESPNOW Not Init");
} else if (delStatus == ESP_ERR_ESPNOW_ARG) {
Serial.println("Invalid Argument");
} else if (delStatus == ESP_ERR_ESPNOW_NOT_FOUND) {
Serial.println("Peer not found.");
} else {
Serial.println("Not sure what happened");
}
}
uint8_t data = 0;
// send data
void sendData() {
data++;
const uint8_t *peer_addr = slave.peer_addr;
Serial.print("Sending: "); Serial.println(data);
esp_err_t result = esp_now_send(peer_addr, &data, sizeof(data));
Serial.print("Send Status: ");
if (result == ESP_OK) {
Serial.println("Success");
} else if (result == ESP_ERR_ESPNOW_NOT_INIT) {
// How did we get so far!!
Serial.println("ESPNOW not Init.");
} else if (result == ESP_ERR_ESPNOW_ARG) {
Serial.println("Invalid Argument");
} else if (result == ESP_ERR_ESPNOW_INTERNAL) {
Serial.println("Internal Error");
} else if (result == ESP_ERR_ESPNOW_NO_MEM) {
Serial.println("ESP_ERR_ESPNOW_NO_MEM");
} else if (result == ESP_ERR_ESPNOW_NOT_FOUND) {
Serial.println("Peer not found.");
} else {
Serial.println("Not sure what happened");
}
}
// callback when data is sent from Master to Slave
void OnDataSent(const uint8_t *mac_addr, esp_now_send_status_t status) {
char macStr[18];
snprintf(macStr, sizeof(macStr), "%02x:%02x:%02x:%02x:%02x:%02x",
mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);
Serial.print("Last Packet Sent to: "); Serial.println(macStr);
Serial.print("Last Packet Send Status: "); Serial.println(status == ESP_NOW_SEND_SUCCESS ? "Delivery Success" : "Delivery Fail");
}
void setup() {
Serial.begin(115200);
//Set device in STA mode to begin with
WiFi.mode(WIFI_STA);
esp_wifi_set_channel(CHANNEL, WIFI_SECOND_CHAN_NONE);
Serial.println("ESPNow/Basic/Master Example");
// This is the mac address of the Master in Station Mode
Serial.print("STA MAC: "); Serial.println(WiFi.macAddress());
Serial.print("STA CHANNEL "); Serial.println(WiFi.channel());
// Init ESPNow with a fallback logic
InitESPNow();
// Once ESPNow is successfully Init, we will register for Send CB to
// get the status of Trasnmitted packet
esp_now_register_send_cb(OnDataSent);
//pinMode(LED_BUILTIN, OUTPUT); // SPC
pinMode(0, OUTPUT); // SPC
//pinMode(5, OUTPUT); // SPC
analogReadResolution(8); // SPC
}
void loop() {
// In the loop we scan for slave
digitalWrite(5, HIGH);
ScanForSlave();
// If Slave is found, it would be populate in `slave` variable
// We will check if `slave` is defined and then we proceed further
if (slave.channel == CHANNEL) { // check if slave channel is defined
// `slave` is defined
// Add slave as peer if it has not been added already
bool isPaired = manageSlave();
if (isPaired) {
// pair success or already paired
// Send data to device
sendData();
digitalWrite(0, data);
} else {
// slave pair failed
Serial.println("Slave pair failed!");
}
}
else {
// No slave found to process
digitalWrite(LED_BUILTIN, LOW);
}
int sensorValue = analogRead(4);
// float voltage = sensorValue * (255.0 / 1023.0);
// Serial.println(voltage);
analogWrite(5, HIGH);
data = sensorValue;
// wait for 'data' seconds to run the logic again
delay(data);
analogWrite(5, LOW);
delay(data);
}
And if you're curious, it's to control this.
