Hello everyone,
I'm a newcomer to this field and would like to ask for some guidance from all the experts here. I'm working on a project for a 3-phase energy meter using the ADE7758 and an ESP32-S3. I've hit a major roadblock with getting the chip to output accurate readings. The values I'm getting are often garbled or simply zero.
I've performed some initial troubleshooting and believe the fundamental communication signals are working correctly:
Troubleshooting Steps I've Taken
- Chip Select (!CS) & Clock (CLK): I've used an oscilloscope to measure the signals on the CS and CLK pins. I can confirm that the ESP32-S3 is correctly pulling the !CS pin LOW and sending a stable CLK signal. This suggests that my basic SPI connections are working as they should.
- Sine Wave Test: For a basic test, I've fed a 50Hz sine wave into the ADE7758's voltage channel (Phase A). However, the readings I get are still highly abnormal and inaccurate.
I suspect that the problem is more complex than a simple wiring mistake. I believe it lies within the code's protocol-level communication and chip configuration.
My Suspicions
- Incomplete Chip Initialization: I am not confident that I have correctly written to the essential registers, such as OPMODE and MMODE, to enable the chip's measurement functions.
- Incorrect SPI Mode: I am unsure if I've set the correct SPI mode (
CPOL/CPHA) in my code to match the ADE7758's requirements.
I've attached the code I am using. Please bear with me, as I am a beginner, and some parts of my code might be frustrating to look at. I would greatly appreciate any advice on what I might be missing or what specific parts of my code I should be focusing on.
#include <Arduino.h>
#include <SPI.h>
// ESP32-S3 SPI pins
#define PIN_MISO 37
#define PIN_MOSI 35
#define PIN_SCK 36
#define PIN_CS 39
SPIClass vspi(FSPI);
SPISettings spiSettings(1000000, MSBFIRST, SPI_MODE1);
// ------------------- Function ------------------- //
uint32_t readRegister24(uint8_t reg) {
vspi.beginTransaction(spiSettings);
digitalWrite(PIN_CS, LOW);
Serial.println("CS LOW");
vspi.transfer(0x80 | reg); // bit7=1 → READ
uint32_t value = 0;
value |= ((uint32_t)vspi.transfer(0)) << 16;
value |= ((uint32_t)vspi.transfer(0)) << 8;
value |= ((uint32_t)vspi.transfer(0));
digitalWrite(PIN_CS, HIGH);
Serial.println("CS HIGH");
vspi.endTransaction();
return value;
}
uint8_t readRegister8(uint8_t reg) {
vspi.beginTransaction(spiSettings);
digitalWrite(PIN_CS, LOW);
Serial.println("CS LOW");
vspi.transfer(0x80 | reg);
uint8_t value = vspi.transfer(0);
digitalWrite(PIN_CS, HIGH);
Serial.println("CS HIGH");
vspi.endTransaction();
return value;
}
// ------------------- Config ------------------- //
// Divider ratio (250k x4 + 1k)
const float dividerRatio = (1000000.0 + 1000.0) / 1000.0; // ≈ 1001
//calibration: 1 LSB = 1 mV
const float VRMS_LSB = 0.001;
// ---------------------------------------------- //
// ------------------- Setup ------------------- //
void setup() {
Serial.begin(115200);
vspi.begin(PIN_SCK, PIN_MISO, PIN_MOSI, -1);
pinMode(PIN_CS, OUTPUT);
digitalWrite(PIN_CS, HIGH);
Serial.println("ESP32-S3 ADE7758 Direct SPI Test");
}
// ------------------- Loop ------------------- //
void loop() {
static unsigned long lastMillis = 0;
if (millis() - lastMillis >= 1000) {
lastMillis = millis();
// VRMS Register
uint32_t vA = readRegister24(0x17);
uint32_t vB = readRegister24(0x18);
uint32_t vC = readRegister24(0x19);
// STATUS Register
uint8_t status = readRegister8(0x0B);
Serial.println("----------------------------------");
Serial.print("STATUS Reg: 0x"); Serial.println(status, HEX);
Serial.print("VRMS Phase A (raw): "); Serial.println(vA);
Serial.print("VRMS Phase B (raw): "); Serial.println(vB);
Serial.print("VRMS Phase C (raw): "); Serial.println(vC);
Serial.println("VOLTAGE RMS readings (calculated V):");
Serial.print("Phase A: "); Serial.println(vA * VRMS_LSB * dividerRatio, 2);
Serial.print("Phase B: "); Serial.println(vB * VRMS_LSB * dividerRatio, 2);
Serial.print("Phase C: "); Serial.println(vC * VRMS_LSB * dividerRatio, 2); } }
Thank you in advance for your help
