How to get battery volt / percentage message send to mqtt?

[gohan]

@mr_sensor said in How to get battery volt / percentage message send to mqtt?:

int oldBatteryPcnt = 0;

I think this needs to be a global variable, not inside loop, otherwise you set it to zero on each loop. I don't have my code with me at the moment to compare, but I think there is an error on the voltage and percentage calculation

[Yveaux]

@gohan said in How to get battery volt / percentage message send to mqtt?:

I think this needs to be a global variable

Or prefix it with the 'static' keyword to indicate its value should persist over multiple runs.

[Mr_sensor]

@yveaux changed the position of int oldBatteryPcnt = 0; outside of the loop and added the static prefix static int oldBatteryPcnt = 0;
Still not giving me the right result the first message seem ok but than it only has 0 ?

Child ID 2Battery Voltage: 0.43 V
Battery Percent: 12 %
2289 TSF:MSG:SEND,2-2-0-0,s=255,c=3,t=0,pt=1,l=1,sg=0,ft=0,st=OK:12
2297 MCO:SLP:MS=60000,SMS=0,I1=255,M1=255,I2=255,M2=255
2304 TSF:TDI:TSL
2306 MCO:SLP:WUP=-1
2308 TSF:TRI:TSB
2363 TSF:MSG:SEND,2-2-0-0,s=1,c=1,t=0,pt=7,l=5,sg=0,ft=0,st=OK:19.6
T: 19.56
2396 TSF:MSG:SEND,2-2-0-0,s=0,c=1,t=1,pt=7,l=5,sg=0,ft=0,st=OK:39.7
H: 39.69
0
Child ID 2Battery Voltage: 0.00 V
Battery Percent: 0 %
2408 TSF:MSG:SEND,2-2-0-0,s=255,c=3,t=0,pt=1,l=1,sg=0,ft=0,st=OK:0
2414 MCO:SLP:MS=60000,SMS=0,I1=255,M1=255,I2=255,M2=255
2420 TSF:TDI:TSL
2422 MCO:SLP:WUP=-1
2426 TSF:TRI:TSB
2482 TSF:MSG:SEND,2-2-0-0,s=1,c=1,t=0,pt=7,l=5,sg=0,ft=0,st=OK:19.6
T: 19.57
2512 TSF:MSG:SEND,2-2-0-0,s=0,c=1,t=1,pt=7,l=5,sg=0,ft=0,st=OK:39.5
H: 39.52
0
Child ID 2Battery Voltage: 0.00 V
Battery Percent: 0 %
2523 MCO:SLP:MS=60000,SMS=0,I1=255,M1=255,I2=255,M2=255
2531 TSF:TDI:TSL```

[gohan]

it looks as the analogread keeps returning zero

[Mr_sensor]

@gohan Tried to find out what causing that but can not figure it out. I'm bot a real coderer so its trial and error :) and trying to understand form other sketches / posts. Any idea where to look for?

[gohan]

try adding a delay(500) before the analogread

[Mr_sensor]

@gohan said in How to get battery volt / percentage message send to mqtt?:

delay(500)

Hi, tried that (already tried it with wait). Now I added it here:

delay(500);
    int sensorValue = analogRead(BATTERY_SENSE_PIN);

Also tried it here:

 if (oldBatteryPcnt != batteryPcnt) {
        // Power up radio after sleep
        delay(500);       
        sendBatteryLevel(batteryPcnt);
        oldBatteryPcnt = batteryPcnt;
    } 
                                                                                                                                                                      
  sleep(SLEEP_TIME); //sleep a bit  ```

Both did not help still ending up with 0 . 
So what should be the best place the right place to put the delay?

[gohan]

the second one is useless. It is odd that it misses the analog reads. What AVR boards version are you using?

[Mr_sensor]

@gohan I'm using the EasyPCB board with an arduino pro mini 3,3v

[gohan]

I mean in Arduino IDE library manager

[Mr_sensor]

@gohan

Arduino Pro or Pro Mini
Programmer AVR ISP
ATmega328P (3,3v 8mhz)

[Mr_sensor]

Still not getting it working! Any thoughts on this?

[gohan]

Try a simple example sketch that reads the analog pin just to make sure the hardware is OK, or try another pro mini

[Mr_sensor]

@gohan Ok will try that see if I made a fault somewhere