Kh8 hybrid modbus help using esp32

[iqbaal77]

Doc: https://github.com/nathanmarlor/foxess_modbus
https://github.com/nathanmarlor/foxess_modbus/wiki/Modbus-Wiring-Guide
https://github.com/nathanmarlor/foxess_modbus/files/11552447/KH.Series.Modbus.pdf
https://github.com/nathanmarlor/foxess_modbus/files/11511264/Energy.Storage.Inverter.Modbus.TCP.Communication.protocols.for.FOXESS-1.pdf

I am beginner trying to get data from foxess kh8 inverter but getting very long data in decimal or HEX using below code, can anyone help me to parse it or get correct readable form or this response is correct or not or how I can get correct response?

rs485 to max485 to esp-wroom-32 ch340 kit
inverter modbus address: 247

I connected:
max485 -> esp32
RO -> RX
(DE + RE common) -> 5 pin
DI -> TX
GND -> GND

My code:

#include <Arduino.h>

#define RX 16      // UART2 RX
#define TX 17      // UART2 TX
#define RTS_pin 5  // RS485 Direction control
#define RS485Transmit HIGH
#define RS485Receive LOW

void setup() {
  pinMode(RTS_pin, OUTPUT);
  digitalWrite(RTS_pin, RS485Receive);

  // Start the Modbus serial Port
  Serial2.begin(9600, SERIAL_8N1, RX, TX);
  Serial.begin(9600);  // Ensure Serial Monitor is set to 9600
  delay(1000);

  Serial.println("Test RS485 Connection");

  while (Serial2.available()) {
    Serial.print(Serial2.read(), HEX);
    Serial.print(" ");
  }

  delay(1000);
}

uint16_t Calc_CRC(uint8_t* message, uint8_t len) {
  uint16_t crc = 0xFFFF;
  for (int pos = 0; pos < len; pos++) {
    crc ^= (uint16_t)message[pos];
    for (int i = 8; i != 0; i--) {
      if ((crc & 0x0001) != 0) {
        crc >>= 1;
        crc ^= 0xA001;
      } else {
        crc >>= 1;
      }
    }
  }
  return crc;
}

String Hex2String(uint8_t num) {
  char hexCar[2];
  sprintf(hexCar, "0x%02X", num);
  return hexCar;
}

void loop() {
  byte request[] = {0xF7 0x03 0x00 0x00 0x00 0x07 0x10 0x9E };

  uint16_t crc = Calc_CRC(request, sizeof(request) - 2);
  request[sizeof(request) - 1] = highByte(crc);
  request[sizeof(request) - 2] = lowByte(crc);

  Serial.println("Schreibe Daten ....");
  for (uint8_t i = 0; i < sizeof(request); i++) {
    Serial.print(Hex2String(request[i]));
    Serial.print(' ');
  }
  Serial.println("");

  digitalWrite(RTS_pin, RS485Transmit);
  Serial2.write(request, sizeof(request));
  Serial2.flush();
  digitalWrite(RTS_pin, RS485Receive);

  delay(100);
  Serial.println("Lese Daten ....");

  while (Serial2.available()) {
    Serial.print(Serial2.read(), HEX);
    Serial.print(" ");
  }
  Serial.println("");
  delay(2000);
}

Serial2.read response:
Schreibe Daten ....
0xF7 0x03 0x00 0x00 0x00 0x07 0x10 0x9E
Lese Daten ....
86 EE 0 0 0 7 1F 1E
or

Schreibe Daten ....
0xF7 0x03 0x00 0x00 0x00 0x07 0x10 0x9E
Lese Daten ....
0 0 0 0 6 0 1 1 C0 E0 E0 60 E1 60 D0 10 70 50 40 40 E0 F1 60 F0 70 60 10 0 70 20 30 28 18 18 18 C C 10 1A 1C E 4 5 2 4 80 E0 C0 60 C0 F0 18 38 18 C E 2 6 4 3 1 E0 C0 E0 54 B0 30 20 70 58 18 1C 18 1C A 2 E E 3 2 C4 B8 0 C0 C0 60 B0 30 78 B0 28 1A C F 60 E0 28 30 18 58 B 1C 8 C 2 B 6 6 E E 7 C0 E0 60 30 38 10 30 38 18 19 8 18 18 A C0 60 30 30 78 98 18 8 4 6 2 E 6 6 7 6 6 42 C0 30 70 20 18 18 C 6 4 3 C0 E0 60 40 20 30 16 0 4C 6 6 7 7 80 C0 60 60 60 30 32 70 90 10 70 70 38 30 18 14 4C 2 2 7 1 1 C0 C0 E0 D0 70 38 0 C 4 7 87 3 1 44 E0 A8 60 70 31 78 30 8 8 A 7 3 1 C0 A0 E0 74 B8 18 4 48 98 C C E 7 3 80 E0 50 D0 40 60 30 70 38 20 30 28 38 38 30 18 10 18 14 1C 6 3 C0 C0 F0 61 10 30 38 30 78 E4 30 B0 F4 E0 E0 E0 F0 F7 E5 F0 A0 F8 E0 E1 E0 F0 E8 F0 F0 F8 78 78 F8 E8 60 F0 B0 E1 E0 F4 F0 F4 F8 34 70 FA 78 7C FE 58 7A FC 7E 78 70 FA F0 7C FC F4 78 F2 F9 E8 FB 9C 7F BE 1C 7E 3F FF 3F 9E 3E C7 BD 7F FF FF FF 9F FB 7E FF BF FF 7F FF DF FF FF FF FF FF BF FF FF FF 7F FF FF FF FF FF FF FF FF BF FF 0 3 0 0 0 0 0 0 6 2 0 0 2 0 0 0 0

[canton7]

There are a few issues with your code, but nothing which should stop it working for small frames, as far as I can see. None of the data you got back looks like a valid modbus frame though.

Try just enabling the pull-up resistor on your rx line? It's going high-z when you transmit, and a floating voltage might be confusing the UART peripheral a bit, but nothing that should lead to a large amount of garbage.

Are you sure you connected to the correct pins on the inverter?

[canton7]

Are you sure you requested register 30000? Can I see your request?

0xF7 0x04 0x79 0x18 0x00 0x0F 0x3D 0xC3 I requested 31000 as per manual let me share 30000 response.

Why did you reply to a message saying to fetch register 30000, with a response to register 31000? How was I supposed to guess that the response you posted was for register 31000? I wasted a chunk of time trying to decode that as register 30000.

Anyway:

0xF7 0x04 0x1E 0x0A 0x3E 0x00 0x39 0x05 0xE1 0x0A 0x68 0x00 0x39 0x05 0xFA 0x00 0x08 0x00 0x00 0x00 0x00 0x00 0x00 0x08 0xFC 0x00 0x7C 0x00 0x00 0x13 0x87 0x00 0x00 0x24 0x27

F7: Slave ID
04: Read input registers (I did say to read holding registers, but some inverters expose registers as both)
1E: 30 bytes of response
0A3E: PV1 voltage: 2662. Scale is V*10, so this is 266.2V
0039: PV1 current: 57. Scale is A*10, so this is 5.7A
05E1: PV1 power: 1505. Scale is W, so this is 1.505kW.

And so on.

[iqbaal77]

I'm really sorry for my mistake, can you please share how I can match registers with each output?

[canton7]

I just worked through an example of decoding the first 3 registers in your response (31000, 31001, 31002). What about that example did you not understand?

[iqbaal77]

I just worked through an example of decoding the first 3 registers in your response (31000, 31001, 31002). What about that example did you not understand?

I got that 100% just wanted to ask correct manual for all registers that you are following.

[canton7]

I'm not sure what you mean. The registers are all listed in the protocol document which you linked to at the top of this discussion.