New srm5.0 meter sends out telegrams without delay.

[macron0]

Hi,

I have been trying this project with and esp01 and my slimemeter iskra smr 5.0 am550-ED1
Where every one says the p1 spits out a telegram every 10 seconds my seems to spit it out non stop.
This seems to make my esp01 crash in about 10 minutes (overheating?) and I have trouble reading the results.
I tried adding an opto coupler and driving it by pulling gpio0 low to set RTS high via 3.3v -> 220K -> pc817 -> gpio0
This sort or works. When RTS is high P1 starts spitting out stuff but it looks incomplete?
But I don't know when to set high and low?
Is a telegram online one line? Or if a telegram one set of lines?
Should I put RTS Low directly after seting it high or wait for the readtelegram loop to finish?
But I had situation it just kept running for a minute and then go low. and sometimes I missed the fasctI set it high.

Here is my version of readTelegram:

`void readTelegram() {
  // DTR is gpio0 and should be pulled low to set RTS high. 
  unsigned long now=millis();  
  if ((unsigned long)(now - lasttelegram) >= 5000) {lasttelegram=now;} else {return;} // only run once every 5 seconds.     
  TIMES1++;  // count the times set RTS was set high.
  digitalWrite(DTR,LOW); // Trigger a telegram (RTS)
  delay(20); // Do we even need a delay?
  if (mySerial.available()) {
    memset(telegram, 0, sizeof(telegram));
    while (mySerial.available()) {
      // digitalWrite(DTR,HIGH); //Should I set RTS Off again> 
      int len = mySerial.readBytesUntil('\n', telegram, MAXLINELENGTH);
      telegram[len] = '\n';
      telegram[len+1] = 0;
      yield();
      if(decodeTelegram(len+1))
      {
         UpdateElectricity();
         //UpdateGas(); // I have no gas. 
      }
    }     
  }
  TIMES2++; // Count the number of times RTS was set LOW. 
  digitalWrite(DTR,HIGH);
}`

At the start of decodeTelegram I log the received data via a post request to my local webserver. I cannot get Serial and Software Serial to work together so I have no other way to log. Maybe this takes to much time and makes the readTelegram to miss data?

bool decodeTelegram(int len) {
  koffiepost(telegram);
  etc...


void koffiepost(char* message)
  {
  String postData="LOW "+String(TIMES1)+"HIGH "+String(TIMES2)+"log="+String(message);
  String address = "http://192.168.0.1/dmation/esplog.html"; 
  HTTPClient http; 
  http.begin(address); 
  http.addHeader("Content-Type", "application/x-www-form-urlencoded"); 
  auto httpCode = http.POST(postData); 
  String payload = http.getString(); 
  http.end();    
  }
  

Some of the output I got. (it seems to only do 3 ort 4 lines and than restarts)

1-3:0.2.8(50)
0-0:1.0.0(200814002323S)
0-/ISK5\2M550E-1013

1-3:0.2.8(50)
0-0:1.0.0(200814002328S)
0-0:96.1.1(4530303533æ
/ISK5\2M550E-1013

1-3:0.2.8(50)
0-0:1.0.0(200814002333S)
0-/ISK5\2M550E-1013

1-3:0.2.8(50)
0-0:1.0.0(200814002338S)
0-0:96.1.1(4530303533þ

Any suggestion in what I could try to get my iskra smr 5.0 am550-ED1 to work with the esp01 and domoticz?

[macron0]

To whom it might concern.

I added a serial inverter using an 2n222a transistor. 2 times 2.2k and one 1k resistor like the level shifter/inverter from this picture: https://willem.aandewiel.nl/wp-content/uploads/2018/08/Schema_V20.png (I did not have the bc547) and i removed the softwareSerial code/lib. The softwareSerial should have replaced the inverter circuit which would have been super cool but apparently 115200 baud is way to fast for it?
Anyway I get data now. Now I need to change the parser to match the iskra smr 5.0 am550-ED1 output.

One more thing. I thought that the iskra was sending data non stop but it turns out it is sending data every second instead of every 10 seconds in the older versions. If I set RST high and keep it HIGH I see short data bursts on my (very simpel) DSO150 every second. Since serial is only listening it seems it just pushes all date in one burt (telegram?)

I am sure we can still read P1 slimmemeter with an ESP01.

Since I only have ld phone j11 plugs which have r pins wired instead of 6 I am using an external usb charger topower the esp.
I added a buck/boost x to 3.3 converter. But once aliexpress delivers my j11 6p plugs I will to to power from the p1 port.

Sample of my log:

LOW 43HIGH 43log=status=alive
LOW 44HIGH 43log=2.7.0(00.000kW)M
LOW 44HIGH 43log=0-0:96.7.21(00007)M
LOW 44HIGH 43log=0-0:96.7.9(00003)M
LOW 44HIGH 43log=1-0:99.97.0(1)(0-0:96.7.19)(191204090823W)(0000000234s)M
LOW 44HIGH 43log=1-0:32.32.0(00004)M
LOW 44HIGH 43log=1-0:32.36.0(00001)M
LOW 44HIGH 43log=0-0:96.13.0()M
LOW 44HIGH 43log=1-0:32.7.0(232.2V)M
LOW 44HIGH 43log=1-0:31.7.0(001A)M
LOW 44HIGH 43log=1-0:21.7.0(00.328kW)M
LOW 44HIGH 43log=1-0:22.7.0(00.000kW)M
LOW 44HIGH 43log=!8715M
LOW 44HIGH 44log=status=alive

Ps,

As far as I could find out the esp8266 IS 5 volt tollerant on most IO ports. So level shifting should not be needed.

[martijnvwezel]

You are correct I experience the same issue, because there is no delay a the softserial is having difficulties, with sscanf I get some descend results, but it misses some the gas part.

[mspoorendonk]

I noticed the same. Softserial has a hard time keeping up with 100k baud. This caused the hardware watchdog timer to reset my wemos D1 mini. I switched to using hardware serial and then everything worked flawlessly.

This is the line I constructed for setting up the inverted serial port. (Such that I don't need an external hardware invertor in the serial line)
Serial.begin(115200, SERIAL_8N1, SERIAL_RX_ONLY, -1, true); // This connects to the RX pin on the wemos D1 mini. We cannot choose a different one.