Receiving garbage data

[sasi143]

Actual data:
bytearray(b'{waterLevel:71,name:TAOF0201,solenoidState:0,valid:1,ultrasonicState:1,waterLevelDistance:43,freeMemory:38,compareStatus:0}')

"Received data:"
Received (raw bytes): bytearray(b"+w4\xb4irL\xa9v\xa5l:7\x11.Lame:TAOF5b51,solenoidState:0,valid:1Lulr\xfa\xf9wonicState:1,waterLevelDistance:43,freeMemory:38,coe\xf8a'`\x06tatus:0}")

I am receiving the above data instead of actual data, some times data was printing correct and some times it behaving strangely. please help me with this.

I am using Arduino uno for client and Raspberry pi for the server with RFM9x

Thankyou

[ladyada]

try sending shorter chunks until you can figure out where the issue is

[sasi143]

My Arduino can able to receive the data perfectly, but Raspberry pi receiving data in garbage format

[jerryneedell]

@sasi143 -- What library are you using on the Arduino? can you post the code you are running on both ends? What pins are you using on the Raspberry Pi?

[sasi143]

Here is my client code (Arduino uno)
`#include <SPI.h>
#include <RH_RF95.h>

#define RFM95_CS 10
#define RFM95_RST 9
#define RFM95_INT 2

#define RF95_FREQ 868.0

const unsigned int TRIG_PIN = 8;
const unsigned int ECHO_PIN = 9;
const unsigned int SOLE_PIN = 5;

char TankName[] = "TAOF0201";

const unsigned int MaxTankHeight = 110;
const unsigned int MinTankHeight = 15;

unsigned int Samples = 10;
char ValveCuttOff = 90;
char ValveOpen = 75;
const unsigned int ErrCheck = 120;

unsigned long duration = 0;
bool verify = true;
bool compareState = false;
bool solenoidValveState = false;
bool storeDurationValue = false;
bool ultraBeat = false;
unsigned long previousDurationValue = 0;
unsigned long previousMillis = 0;
const long interval = 1000;

// Singleton instance of the radio driver
RH_RF95 rf95(RFM95_CS, RFM95_INT);

void setup()
{
pinMode(RFM95_RST, OUTPUT);
digitalWrite(RFM95_RST, HIGH);

while (!Serial);
Serial.begin(9600);
delay(100);

Serial.println(F("Arduino LoRa TX Node!"));

pinMode(TRIG_PIN, OUTPUT);
pinMode(ECHO_PIN, INPUT);
pinMode(SOLE_PIN, OUTPUT);
// manual reset
digitalWrite(RFM95_RST, LOW);
delay(10);
digitalWrite(RFM95_RST, HIGH);
delay(10);

while (!rf95.init()) {
Serial.println("LoRa radio init failed");
while (1);
}
Serial.println(F("LoRa radio init OK!"));

// Defaults after init are 434.0MHz, modulation GFSK_Rb250Fd250, +13dbM
if (!rf95.setFrequency(RF95_FREQ)) {
Serial.println(F("setFrequency failed"));
while (1);
}
Serial.print(F("Set Freq to: ")); Serial.println(RF95_FREQ);

// you can set transmitter powers from 5 to 23 dBm:
rf95.setTxPower(23, false);

}

void loop()
{
mainFunction();
loraSubFunction();
}

int freeRam ()
{
extern int __heap_start, *__brkval;
int v;
return (int) &v - (__brkval == 0 ? (int) &__heap_start : (int) __brkval);
}

void mainFunction() {
unsigned long currentMillis = millis();

if ((currentMillis - previousMillis) >= interval) {
// save the last time you blinked the LED
previousMillis = currentMillis;
long errDuration = 0;
int temp = 0;
int percentage = 0;
int durationDifference = 0;
int distance = 0 ;
int AvgSamples = Samples;
int distanceCaliculate = 0;

for (int i = 0; i < AvgSamples; i++)
{
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distanceCaliculate = (duration / 29 ) / 2;
  if ((duration <= 58 * MaxTankHeight) && (duration >= 58 * MinTankHeight))
  {


    if (storeDurationValue == false)
    {
      previousDurationValue = duration;
      storeDurationValue = true;
    }
    durationDifference = duration - previousDurationValue;

    durationDifference = abs(durationDifference);
    if (durationDifference <= ErrCheck)
    {
      previousDurationValue = duration;
      errDuration += duration;
      temp++;
      if (temp == 10) {
        AvgSamples = 0;
        distance = ((errDuration / temp) / 29 ) / 2;
      }


    }
  }

  delay(500);
}

if ((duration > 0) && (distance == 0)) {

  Serial.println(F("-----------------------------Sensor values are not accurate---------------------------------------"));
  percentage = 0;
  verify = false;
  ultraBeat = true;

}

if (duration <= 0) {
  Serial.println(F("Warning: no pulse from sensor"));
  percentage = 0;
  verify = false;
  ultraBeat = false;
}
else {
  Serial.print(F("distance to nearest object:"));
  Serial.println(distance);
  Serial.println(" cm");
  ultraBeat = true;
  if ((distance <= MaxTankHeight) && (distance >= MinTankHeight))
  {

    percentage = map(distance, MinTankHeight, MaxTankHeight, 100, 0);
    verify = true;
    if ((percentage > ValveCuttOff) && (compareState == false))
    {
      digitalWrite(SOLE_PIN, HIGH);
      solenoidValveState = true;
      compareState = true;
      Serial.println(F("----Solenoid Valve turned ON------"));
    }
    else if ((percentage < ValveOpen) && (compareState == true))
    {
      digitalWrite(SOLE_PIN, LOW);
      solenoidValveState = false;
      compareState = false;
      Serial.println(F("----Solenoid Valve turned OFF------"));
    }
  }
  else {
    verify = false;
    percentage = 0;
  }


}

Serial.println(F("Sending to rf95_server"));
int availableRam = map(freeRam(), 0, 3000, 0, 100);
String jsonChar = "{waterLevel:" + (String)percentage + ",name:" + (String)TankName + ",solenoidState:" + (String)solenoidValveState + ",valid:" + (String)verify + ",ultrasonicState:" + (String)ultraBeat + ",waterLevelDistance:" + (String)distanceCaliculate + ",freeMemory:" + (String)availableRam + ",compareStatus:"+(String)compareState+"}";

rf95.send(jsonChar.c_str (), jsonChar.length());

Serial.println(F("Waiting for packet to complete...")); delay(10);
rf95.waitPacketSent();

}

}

void loraSubFunction() {
if (rf95.available())
{
// Should be a message for us now
uint8_t buf[RH_RF95_MAX_MESSAGE_LEN];
uint8_t len = sizeof(buf);

if (rf95.recv(buf, &len))
{
  Serial.println(F("------------------Got reply------------------------"));
  String output = (char*)buf;

  Serial.println(output.substring(0, len));
  if (output.substring(0, len).substring(5, 13) == TankName) {
    if (output.substring(0, len).substring(20, len) == "ON" || output.substring(0, len).substring(20, len) == "OFF")
    {
      if (output.substring(0, len).substring(20, len) == "ON") {
        solenoidValveState = true;
        digitalWrite(SOLE_PIN, HIGH);
      }
      if (output.substring(0, len).substring(20, len) == "OFF") {
        solenoidValveState = false;
        digitalWrite(SOLE_PIN, LOW);
      }



      rf95.send("{Tank:TAOF0301,state:success}", 29);
    }
    Serial.println();
  }
}

}
}`
connected pins on arduino uno from rfm9x:
cs - 10
mosi - 11
miso - 12
sck- 13
g0 - 2
gnd - gnd
vin - 3.3
Rst - None(Not connected)

My Raspberry pi code :
`import board
import busio
import digitalio
import time
import adafruit_rfm9x

Define radio parameters.

RADIO_FREQ_MHZ = 868.0 # Frequency of the radio in Mhz. Must match your
# module! Can be a value like 915.0, 433.0, etc.

Define pins connected to the chip, use these if wiring up the breakout according to the guide:

CS = digitalio.DigitalInOut(board.D5)
RESET = digitalio.DigitalInOut(board.D6)

Initialize SPI bus.

spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)

Initialze RFM radio

rfm9x = adafruit_rfm9x.RFM9x(spi, CS, RESET, RADIO_FREQ_MHZ,baudrate=1000000)

rfm9x.tx_power = 23

while True:
# Optionally change the receive timeout from its default of 0.5 seconds:
packet = rfm9x.receive(timeout=2.0)
# If no packet was received during the timeout then None is returned.
if packet is None:
#print('Received nothing! Listening again...')
None
else:
#packet_text = str(packet, "utf-8")
print('Received (raw bytes): {0}\n'.format(packet))
rssi = rfm9x.rssi
print('Received signal strength: {0} dB'.format(rssi))`

connected pins from rfm9x to raspberry pi3:

cs - 29
mosi - 20
miso - 21
sck- 23
g0 - None(not conneted)
gnd - 25
vin - 17
Rst - 31

[jerryneedell]

A few suggestions:

1. try removing the baud rate setting here:

rfm9x = adafruit_rfm9x.RFM9x(spi, CS, RESET, RADIO_FREQ_MHZ,baudrate=1000000)

use
rfm9x = adafruit_rfm9x.RFM9x(spi, CS, RESET, RADIO_FREQ_MHZ)

It is not clear why you are lowering the baud rate to 1Mhz from the default 5Mhz

If that does not help then as @ladyada suggested, try sending shorter packets just to see if they work reliably and if they do increase the size to see if there is a threshold where it fails.

also - how often are you sending these packets. ti looks like the interval s 1 second. - If so, that may be an issue with the receive timeout of 2 seconds. Try slowing down the transit rate to see if that helps.
Good luck!

[sasi143]

@jerryneedell , @ladyada I did below the things that you suggested.

1. Reduced transmitting data size from 128 bytes to 18 bytes.
2. Increased transmitting time from 1 second to 3 minutes
3. Changed baud rate to 5Mhz as default
4. Received timeout parameter changed to default(0.2 seconds) in python code(Gateway)

Now I am getting data like this:

bytearray(b'| \xea\x81q\x9e\x86\x02\xffZ\xe0uQ\xd0\xf6\nV3\x1c>\xb7\x9b\x90\x86\xed\x05*\xe5\xe1\xee\xf4$\xf1\xb0\x1f\xb1\x86\xc3\xf5\t?\x80syr\xac\xa7\x0b\x1f\xb01(5\xf0\x0e4\x8eB\xbb\x1a~\x1c\x9c\x0b\x9a\x11`\xd2\xd2-\x16\xe0Le\x9b@t\xc4\xd3~\x18Eol\xfdM#k\xf2\xde\x9e\xca\xa5\xa2\xa7#5l\x98\x0c&M\xd2\x8a\xa6\x0f\x0e\xba\x95\xb0b;"\xe8\x94A\xa5Q\xbf\xc7Q\xa5\x04\xf2H"\xf1\xe3m\\x1d6C\x80\x19=\xfa\xbf\x12\xd0\xa0\x95\xed\xc2K\xfae')

Actuall data is :

bytearray(b'121,0,0,0,0,0,43,0')

Sometimes I can able to receive the data correct and sometimes it behaves strangely. Please suggest on the same

[sasi143]

can someone please respond?

[jerryneedell]

I have no idea what is going on. When you say it works sometimes, does to run for awhile then start giving the bad data? Are you sure you don't have something else transmitting? I know I often see bursts of data that I don't recognize if I just listen.
But I have not seen problems similar to what you are describing. Have you tried just using the basic test programs on both units just to verify basic function?

When you say the Arduino receives data OK, what data is that? Is it being sent from the Raspberry Pi?

For your tests, are the radios near each other and are you just using simple wire antennas?

[sasi143]

@jerryneedell Thanks for responding quickly. I am sure it was not sending any bad data because at the same time I can able to receive the data perfectly in Arduino uno. The basic functionality is failing some times.

I am sending plain string data from Arduino uno(client) to raspberry pi(gateway)

I am using this type of Antena : https://www.adafruit.com/product/3340

If possible can you please help me to run this code : https://github.com/hallard/RadioHead/blob/master/examples/raspi/rf95/rf95_server.cpp

when I run the code it saying :

RF95 module init failed, Please verify wiring/module
RF95 CS=GPIO25, IRQ=GPIO4, RST=GPIO17, LED=GPIO255

I didn't find IRQ and LED pin on LoRA module.

can you please help me on this.
Thank you

[jerryneedell]

@sasi143 I have not used the RadioHead library on my RaspBerry Pi at all. I have only used the CircuitPython RFM9X library for LoRa.

The LED pin is , Think just for an external LED if you want to use one -- you don't need it.
The IRQ pin on the LoRa Module is the pin labeled G0 if you are using one of these boards
https://www.adafruit.com/product/3072

On the Arduino are you using the adafruit fork of the Radiohead library? https://github.com/adafruit/RadioHead
That is what I have used.

When you say the Arduino is receiving data, where is the data coming from?

Have you ever been able to communicate with the Raspberry Pi system?

[sasi143]

I am using the same product and the same library that you asked.

one arduino uno-1 (client) sending the data. I am running receiving the code in both Raspberry pi(Python) and arduino uno -2.

I can able to communicate raspberry pi with the only python, but still failing to run Radio head c++ files in the raspberry pi

[jerryneedell]

OK -- so when you use the adafruit-circuitpython-rfm9x library on the Raspberry PI, you can receive data reliably? It is just the c++ library that is not working? Is that correct?

[sasi143]

No, I can able to receive the data in Raspberry pi but it was not consistent manner. sometimes I am receiving data good and some times it was behaving strangely.

Good data : bytearray(b'121,56,0,1,1,57,43,0')
Strange data :
bytearray(b"\xd3\xd1\xe6\x0f\xbey\x08\x1b\x90\x1a\x97\x10\xff- Z\x85r\xa8K\xcbJ\xe2\x11\x96\x06\xc06\xd2\x81\xc6\xdf\xd0\x1d\x95\xe1?\x97_-\xb6^ncl\'V\x11\xe4\xbaU\x9eF)\x94\xac\x1c\x9ci(\xa6\x1a+\xb2d\xd6 \xa5u>\xfb\xb8zwZ\xa5\xb9\x12\xfa\x81\xce\xc1*o\xe9A\xb3\x95\x1a\xc7\xf0G2\xb7\xa0\x90\xf0$|\xcfG;,\xbdo\xc1\xe0\x8a{\x96[\xcf\x7f\x08\xc3x.RM6\xdc\x1c|\xb8\xc8\xb7\x8e\x84\xbb\x96")

so, python library was not consistently printing the right data. so, I am thinking to move to c++ program on raspberry pi which was build in RadioHead library
Link : https://github.com/adafruit/RadioHead/tree/master/examples/raspi

But, when I try to run "RasPiRH.cpp" file in Raspberry pi it saying "RF95 module init failed, Please verify wiring/module"

[jerryneedell]

ah -- how often do you get the bad packets? -- as I mentioned I do see something similar -- very infrequently -- many minutes apart -- I will get a packet like this

Received (raw bytes): bytearray(b'Zr\xee\x1b&\xb3\x14\x0c\xa4 \xd1\xd8No\xe7\x16\xf0\x12\x04\x06\x11\xb6\x9a\x89\r\x82\x0b0\xbf99\x0e\xabb\xf7\x0e,v\xfa J\x80\xc3x\xf2I\xb0g\nO\xf4\xf4\x9cc\xea\x0b\xb2\xaf8\x8b\x9a\xce\xda\xfe\xfba\x8a\x99\xd3\x08\xe3w37\xa9\xc3\x963\x8f\xa1\x00\x8b\xdc\xcb\x81\x1e)g.\xf3\xbaa\xaaC\xe8\xb0\x10\xd9\xb2\x11H\xdbO\xf2\r\xf5D\xc1+\xbd\x8d\xd1\xf2\x7f\x8e\xe1\xb5\xc9\x13\x87X\xd4\x941e\x81DQ-$\x98\x0c2\x9b\x12s\xc8\xe1\xbf\x88\xceu/`\xe1A\r\xc5-\x8b\x8f\xd8\x12\xc1)\xf6\xe0E&\xce\xb2\xad\x8b\xfe\xdd\xb9\x92\xcd\x15r\xa6')
Received signal strength: -86 dB

I get these if I just listen without anything transmitting.
I have not been able to determine the source. I just ignore them - I use the packet headers to filter them out.

Is this what you are seeing or do the bad packets correspond to the times of your actual transmissions? I think that is what you stated in your first message, so I was not thinking it was comparable, but it may be.
Since the bad packets you report are not even close in length to your transmitted packet, I am confused how they can be related.

If I have time, I can take a look at the c++ library this weekend,

[sasi143]

once again thanks for the quick response,

sometimes my transmitting data can be manipulated like below

bytearray(b'121,56,0,1,1,5>,4\xa3\xb59')

some values are correct in that data and some index values are filled up garbage values

I am really appreciate your kind response