Flowcode Support Board

Hi,
I have been looking at the enviroment monitor demo which is close to what I am looking for. The bit I am not happy with is the line chart as when it is full it carries on showing new data but the x axis compresses so over time it will get unreadable.
I would like to have a scrolling chart of the last x samples, I changed the x axis autoscale to "no" but that just meant that as soon as the chart was full it stopped showing live data.
I have a thought that to do what i require I need to write the data to a FIFO buffer and then write the contents to the chart.
This seems like a lot of work and possibly will make the display very slow so I wondered if I am on the right lines or if anyone has any better solution.

Regards,
Bob

Hi Bob,

Try the historic chart and hopefully that will do what you need.

Hi Ben

Admittedly I'm thicker than a porridge milk shake but I can't see any historic chart option in Web Developer.

Regards

Hi Iain.
Historic chart is within PC developer, which the environmental monitor demo uses.

Hi Martin

Thanks. Glad to hear I'm not such an idiot after all I really should get back into Web / PC developer as I've not touched it in a long while. It is such a useful feature.

Regards

Hi Martin,
Unfortunately I need something for the web developer. I am assuming there are technical reasons why this and xy chart and circular buffers are not in web developer.

Regards,
Bob

Hi Ben,
Is there any chance the historic chart will be available for the web developer. I have thought about string it in a circular buffer but sending over 2000 values every 4 seconds to update the chart does not seem to be a practical solution.

Regards,
Bob

Web Developer projects are very different to PC Developer and Embedded projects in Flowcode. We are investigating a scrolling historic chart for Web Developer, but it might be too slow to be useful.

Hi Steve,
A long time ago I had a chart working for this monitor, it was created in node red and ran on the Pi as far as I can recall.
I can understand it being slow if the web app was loaded onto a mobile phone but not sure if this would be the same problem if the Pi or ESP32 etc is hosting the web app?

Bob

My thinking is it's the speed of receiving the data that is the bottleneck rather than the speed of the device hosting the app.

What are your requirements for a scrolling chart in terms of throughput (number of datapoints per second and number of datapoints on the chart as a whole)? That might help guide us when we do some investigating.