python script to signalk

[jamos.tan@gmail.com]

Found this example in openplotter example tools:

Code:

#!/usr/bin/python
'''
//Arduino code
int i=0;
// the setup routine runs once when you press reset:
void setup() {
 Serial.begin(9600);
}

void loop() {
 if (i>100) i=0;
 i++;
 Serial.print("ArduinoValue:");
 Serial.println(i);
 delay(300);        // delay in between reads for stability
}
'''

import signal, sys, time, socket, datetime, subprocess, math, serial

# Control-C signal handler to suppress exceptions if user presses Control C
# This is totally optional.
def signal_handler(sig, frame):
    print('You pressed Ctrl+C!!!!')
    sys.exit(0)
    
# init
signal.signal(signal.SIGINT, signal_handler)
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
ser = serial.Serial('/dev/ttyOP_LEONARDO', 9600, timeout=1)
ser.flush()

Value = 0            
# forever loop until user presses Control-C
while 1:    
    serLine = ser.readline()
    if 'ArduinoValue:' in serLine:
        Value = serLine[13:-1]
        #print Value
        
    SignalK = '{"updates": [{"$source":"OPserial.BAT.V1","values":[{"path": "electrical.batteries.main.voltage","value":'+str(Value)+'}]}]}\n'
    #print SignalK
    sock.sendto(SignalK, ('localhost', 55559))
    time.sleep(0.300)

This code seems to include a serial connection with an arduino, and maps it to the signalk path that I want.
I have changed the code to include the details of my original script:

Code:

#!/usr/bin/python
'''
//Arduino code
int i=0;
// the setup routine runs once when you press reset:
void setup() {
 Serial.begin(38400);
}

void loop() {
 if (i>100) i=0;
 i++;
 Serial.print("sp3_ADC_OUTPUT");
 Serial.println(i);
 delay(300);        // delay in between reads for stability
}
'''

import signal, sys, time, socket, datetime, subprocess, math, serial

# Control-C signal handler to suppress exceptions if user presses Control C
# This is totally optional.
def signal_handler(sig, frame):
    print('You pressed Ctrl+C!!!!')
    sys.exit(0)
    
# init
signal.signal(signal.SIGINT, signal_handler)
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
ser = serial.Serial('/dev/serial0', 38400, timeout=1)
ser.flush()

Value = 0            
# forever loop until user presses Control-C
while 1:    
    serLine = ser.readline()
    if 'sp3_ADC_OUTPUT' in serLine:
        Value = serLine[13:-1]
        #print Value
        
    SignalK = '{"updates": [{"$source":"OPserial.BAT.V1","values":[{"path": "electrical.batteries.main.voltage","value":'+str(Value)+'}]}]}\n'
    #print SignalK
    sock.sendto(SignalK, ('localhost', 55559))
    time.sleep(0.300)

The trick is, I don't use an arduino, so I need to play with the baudrate I think.
I'll test it and report back.

---

Ok, started the script from the tools tab in openplotter.
SignalK sentence is now added, but reads as 0V.
Not sure what goes wrong here.