Acurite 899 rain gauge almost working

[Jeff Johnson]

I spent a couple of days trying to make rtl_433 work with the Acurite 899 rain gauge. I seem to have the data reported accurately but I think I'm going to need help getting the data to be posted in csv files (the file type I use for my home weather and solar monitoring system). I must admit, I'm totally lost on how to have the meters readings added to the csv entry generated. If anyone has a tip, please let me know. Once that's working I'd like to submit my update to the acurite source so that others with this sensor can incorporate it in their system.

Jeff

[Robert Terzi]

Is the Acurite 899 the same as the 896 rain guage?    Are you using the same decoder?

Either way, Can you please submit some samples to the rtl_433_tests repo?    If I'm remembering correctly,  there are no 896 samples, and the current implementation generates a lot of false positives.

As far as writing CSV files,  it should be pretty straightforward with -F csv and a tiny bit of shell scripting depending on what you need.  You didn't provide any details.  What OS are you running rtl_433 on?

[Jeff Johnson]

Thanks for the response. As far as I can tell the two gauges (896 and 899) are slightly different. I had to establish a new channel decode, add the 0x30 message type selection, and slightly alter the data decryption for the rain counter. 
Digging a little deeper, the json output seems correct...

{"time" : "2017-12-11 08:29:20", "model" : "Acurite tower sensor", "id" : 14610, "channel" : "A", "temperature_C" : 3.500, "humidity" : 78, "battery" : 0, "status" : 68}

{"time" : "2017-12-11 08:29:24", "model" : "Acurite Rain 899", "id" : 2471, "channel" : "A", "sequence_num" : 2, "battery" : 1, "message_type" : 48, "raincounter_raw" : 1043, "rainfall_accumulation" : 10.430}

however the csv output is missing the sensor data...

2017-12-10 18:35:19,Acurite tower sensor,14610,A,0,10.600,,,,70,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,68,,,,,,,,,,,,,,,,,,,,,,,,,,,,

2017-12-10 18:35:24,Acurite Rain 899,2471,A,1,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

I'll pull some samples to add to the repository as soon as I have time. It will be my first venture down that avenue.

As for my configuration, rtl dongle on a lenovo T510 laptop running Centos 7 (for testing and for home server).

Jeff

[Christian Zuckschwerdt]

acurite.c is broken. The enumeration of possible fields is missing (see `.fields` and `output_fields` in other decoders). CSV will skip undeclared fields.

[Jeff Johnson]

Thanks for the insight. Will take a look.

[Jeff Johnson]

For anyone interested, the changes needed for acurite.c  to support the 899 rain gauge are:

30d29

< #define ACURITE_MSGTYPE_RAINFALL     0x30

176,190d174

< 

< // The high 2 bits of byte zero are the channel (bits 7,6)

< //  00 = A

< //  01 = B

< //  10 = C

< 

< static char chAltLetter[4] = {'A','B','C','E'}; // 'E' stands for error

< 

< static char acurite_getAltChannel(uint8_t byte){

<     int channel = (byte & 0xC0) >> 6;

<     return chAltLetter[channel];

< }

< 

< 

< 

637,656d620

< } else  if (message_type == ACURITE_MSGTYPE_RAINFALL) {

< // Rain fall gauge 899

< //  needs fields and output_fields definitions to create CSV output (see Lacrosse)

< //

< channel = acurite_getAltChannel(bb[0]);

< sprintf(channel_str, "%c", channel);

<         raincounter = acurite_getRainfallCounter(bb[5], bb[6]);

< 

<         data = data_make(

<         "time",          "", DATA_STRING, time_str,

<         "model",        "", DATA_STRING, "Acurite Rain 899",

< "id", "", DATA_INT, sensor_id,

<           "channel",      "", DATA_STRING, &channel_str,

<         "battery",      "Battery ",    DATA_INT, battery_low,

<                 "raincounter_raw", "raincount", DATA_INT,    raincounter,

<                 NULL);

< 

<         data_acquired_handler(data);

< valid++;

< 

1070c1034

<     .disabled       = 0,

---

>     .disabled       = 1,

Still learning git..