I am using a Bluetooth module HC-05 to Stream data from Arduino to My computer. In they computer I am using a python script to receive
They specifications: Baud rate: 9600
But I am getting an error. The right data got in the computer should be:
b'123.098x726.8393x123x\r\n'
Which I almost always get, but sometimes I get the following:
b'123.098x726.8393x123x123.098x726.8393x123\r\n'. wrong
So I don't know happens, in python I use the method reset_input_buffer() and reset_output_buffer() and in Arduino ide I use Serial.flush()
The error keep happens, would it be the baudrate? I increase it would it be the solutionn?
Thanks in advance
String str;
String strs[8];
int pwm=9;
int tech;
String sync_fromApp = "?";
String sync_ok = "okx";
int cyc_num;
int PWM_0;
int PWM_i;
int PWM_f;
float volt;
float cur;
int t;
void setup() {
// put your setup code here, to run once:
TCCR1B = TCCR1B & B11111000 | B00000001;
Serial.begin(9600);
Serial.setTimeout(5);
pinMode(A0, INPUT);
pinMode(pwm, OUTPUT);
analogWrite(pwm, 130);
delay(1000);
}
void loop() {
// put your main code here, to run repeatedly:
int strCount = 0;
if (Serial.available() > 0) {
str = Serial.readString();
str.trim();
if (str == sync_fromApp) {
Serial.println(sync_ok);
//Serial.flush();
}
while (str.length() > 0) {
int index = str.indexOf('x');
if (index == -1) {
strs[strCount++] = str;
break;
}
else {
strs[strCount++] = str.substring(0, index);
str = str.substring(index + 1);
}
}
tech = strs[0].toInt();
float E0 = strs[1].toInt() / 1000.0;
float Ei = strs[2].toInt() / 1000.0;
float Ef = strs[3].toInt() / 1000.0;
cyc_num = strs[4].toInt();
int scan_rate = strs[5].toInt();
int t_chro = strs[6].toInt();
int t_step_chro = strs[7].toInt();
float e00 = ((995.0 / 1986.0) * 5.06 + (995.0 / 1004.0) * E0);
PWM_0 = e00 * (255 / 4.99); //Starting Voltage
float eii = ((995.0 / 1986.0) * 5.06 + (995.0 / 1004.0) * Ei);
PWM_i = eii * (255 / 4.99)-1; //Min Voltage
float eff = ((995.0 / 1986.0) * 5.06 + (995.0 / 1004.0) * Ef);
PWM_f = eff * (255 / 4.99)+1; //Max Voltage
long t = (4990000L) / (256L * scan_rate); //delay scan rate
//default:
analogWrite(pwm, PWM_0);
switch (tech) {
//---Cyclic voltammetry---
case 1:
delay(3000);
for (int n = 1; n <= cyc_num; n++) {
for (int val = PWM_0; val < PWM_f; val++) {
analogWrite(pwm, val);
volt = 0.01974563 * val - 2.558; //0.01974563
cur = 0.51469 * (analogRead(A0)) - 255.226; //254.226
Serial.print(volt, 3);
Serial.print('x');
Serial.print(cur, 3);
Serial.print('x');
Serial.print(val);
Serial.println('x');
Serial.flush();
delay(t);
}
for (int val = PWM_f; val > PWM_i; val--) {
analogWrite(pwm, val);
volt = 0.01974563 * val - 2.558;
cur = 0.50669 * (analogRead(A0)) - 255.226;
//cur_ave = analogRead(A0);
Serial.print(volt, 3);
Serial.print('x');
Serial.print(cur, 3);
Serial.print('x');
Serial.print(val);
Serial.println('x');
Serial.flush();
delay(t);
}
PWM_0 = PWM_i;
//Serial.println(n);
}
Serial.println("Nx");
Serial.flush();
analogWrite(pwm, 130);
tech = 0;
break;
default:
break;
}
}
else {
digitalWrite(13, HIGH);
delay(200);
digitalWrite(13, LOW);
delay(200);
}
}
Above left the arduino sketch.
Below is the python code
self.ser.write(self.parametersToArduino.encode()) #command to start stream
pass
self.ser.reset_input_buffer() #flush input buffer
self.ser.reset_output_buffer() #flush output buffer
COM.stop_button["state"] = "active"
while self.threading:
try:
data.RowMsg = self.ser.readline() # read data from arduino
data.DecodeMsg() #decode data from arduino
if len(data.RowMsg)>0:
if b'N' in data.RowMsg:
#print("It's over")
self.threading = False
break
data.upXData() #update a list to plot
data.upYData() #update a list to plot
self.ser.reset_input_buffer()
self.ser.reset_output_buffer()
pass
pass
except Exception as e:
print(e)
pass
DecodeMsg is the code below
def DecodeMsg(self):
temporal = self.RowMsg.decode('utf8')
if len(temporal)>0:
if "x" in temporal:
self.msg = temporal.split("x")
del self.msg[-1]
pass
print(self.msg) #debugg
pass
pass
