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upgrade rate signalK
#1
Wink 
Hi to everybody,
I am new user of openplotter.
I have connected my raspberry Pi 3B to my boat instrument and I can see data from NMEA 2000 network because I am using both RS485-CAN adapter and also CAN to serial USB (Arduino) adapter. 
In both case I can see the same data at the same rate.
I have started to use also node-red and Influxdb to show and store the data however, at the beginning, I wanted to store and visualize my date at each second. After some tests I have seen that my update frequency of every data (wind, speed, GPS...) is near 2.5 second (see the CSV attached) while data rate of all data are different each other and some run at 10 Hz like GPS.
I have two question:
1. Is it possible to change this data rate or it is an hardware limit?
2. I know my data are stored locally and not in the cloud. Could anyone say to me where is the data folder and which is the format?

I want to thanks the community in advance.

Giuseppe
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#2
(2022-03-30, 04:10 PM)gcaravello Wrote: Hi to everybody,
I am new user of openplotter.
I have connected my raspberry Pi 3B to my boat instrument and I can see data from NMEA 2000 network because I am using both RS485-CAN adapter and also CAN to serial USB (Arduino) adapter. 
In both case I can see the same data at the same rate.
I have started to use also node-red and Influxdb to show and store the data however, at the beginning, I wanted to store and visualize my date at each second. After some tests I have seen that my update frequency of every data (wind, speed, GPS...) is near 2.5 second (see the CSV attached) while data rate of all data are different each other and some run at 10 Hz like GPS.
I have two question:
1. Is it possible to change this data rate or it is an hardware limit?
2. I know my data are stored locally and not in the cloud. Could anyone say to me where is the data folder and which is the format?

I want to thanks the community in advance.

Giuseppe

Are you using node-red to write to influxdb? 

The signalk influxdb write app does it all for you, no need to do anything in node-red.  The data get stored in an influxdb database timestamped at the time it arrived in signalk but the plugin can batch write every x seconds so it writes less often,  you can set how often in the app, timespamps don't change. 
The only way to get to it is through influxdb though chronograf or grafana make that easy.
Reply
#3
(2022-03-30, 05:35 PM)PaddyB Wrote:
(2022-03-30, 04:10 PM)gcaravello Wrote: Hi to everybody,
I am new user of openplotter.
I have connected my raspberry Pi 3B to my boat instrument and I can see data from NMEA 2000 network because I am using both RS485-CAN adapter and also CAN to serial USB (Arduino) adapter. 
In both case I can see the same data at the same rate.
I have started to use also node-red and Influxdb to show and store the data however, at the beginning, I wanted to store and visualize my date at each second. After some tests I have seen that my update frequency of every data (wind, speed, GPS...) is near 2.5 second (see the CSV attached) while data rate of all data are different each other and some run at 10 Hz like GPS.
I have two question:
1. Is it possible to change this data rate or it is an hardware limit?
2. I know my data are stored locally and not in the cloud. Could anyone say to me where is the data folder and which is the format?

I want to thanks the community in advance.

Giuseppe

Are you using node-red to write to influxdb? 

The signalk influxdb write app does it all for you, no need to do anything in node-red.  The data get stored in an influxdb database timestamped at the time it arrived in signalk but the plugin can batch write every x seconds so it writes less often,  you can set how often in the app, timespamps don't change. 
The only way to get to it is through influxdb though chronograf or grafana make that easy.

Thanks you for your reply.
No, I am using the plugin for influxdb l. I use node red only for visualization.
Reply
#4
I think the issue is how you're using node red to display the data. I use KIP for my dashboards, and wind direction (which I update at 10Hz) is actually updated at 10Hz, so I don't think the issue is SignalK-related.

However, data is read by KIP before being inserted to influx (or simultaneously). Since you probably are trying to get realtime data (not historical, but this is just a guess) at 10Hz you can read directly the SignalK inputs in node-red (with a signalk-input-handler or similar).
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#5
(2022-03-30, 09:23 PM)gcaravello Wrote: Thanks you for your reply.
No, I am using the plugin for influxdb l. I use node red only for visualization.

Try grafana or chronograf instead of node-red to view the influxdb data, so much better than node-red.

To check the timestamps try this, in a terminal first start influx, open your database then set the time format and  look at the data,

Code:
pi@openplotter:~ $ influx
Connected to http://localhost:8086 version 1.8.10
InfluxDB shell version: 1.8.10
> use boatDb
Using database boatDb
> precision rfc3339
> SELECT "time", "value"  FROM "environment.wind.speedApparent" limit 5
name: environment.wind.speedApparent
time                     value
----                     -----
2021-12-12T13:34:53.533Z 5.710334779951478
2021-12-12T13:34:54.577Z 5.556001407520357
2021-12-12T13:34:55.642Z 5.298779120135156
2021-12-12T13:34:56.707Z 5.041556832749953
2021-12-12T13:34:57.773Z 5.041556832749953
>
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