Topics

Min/max values for voltage/current meters for LcooNet, Z21, DCC++, Cbus?


danielb987
 

Does anyone knows the minimum and maximum values of voltage and current meters for LocoNet, Z21, DCC++ and CBus?

If you know the resolution too, it would be great, but it's not that important.

DCC++ is measured in percent so I assume the min and max values are 0 and 100.0?

--------------------

The MultiMeter interface specified the unit for current, but not for voltage.

LocoNet is measured in amps. Is voltage measured in volts?

Z21 is measured in milliamps. Is voltage measured in millivolts?

Cbus is measured in milliamps. Is voltage measured in millivolts?

--------------------

Is it bad to add a meter icon to the PanelEditor without making it work on the web panel? I think I can get a meter icon work on the PanelEditor but it will be too much work for me to implement it for the web, partly because I'm not so used to work with web design. I could probably extend a text label or a memory icon to make the web work, but I might also add a graphical icon for displaying a meter that would need more work to work for the web panel.

I attach an image on one idea I have. The image shows two circular icons that shows an AnalogIO that may be a servo or a rotating crane or something like that. Something that rotates around its axle. It may be useful if you for example has a crane next to the track and want to see on the panel which position the crane has to the track. And below these two icons is a voltage/current meter.

Daniel


Andrew Crosland
 

CBUS measurements are sent as 16 bit unsigned integers in the CAN frame,

The current value is in milliAmps with a range of 0 - 65535.

The voltage value is in V*10 so the actual range is 0 - 6553.5 V. This may seem odd but it made the calculations and presentation in other tools easier in a PIC microcontroller.

CbusMultiMeter converts the measurements to floats and calls setCurrent() with milliAmps and setVoltage() with Volts.

Andrew

------ Original Message ------
From: "danielb987" <db123@...>
To: jmri@jmri-developers.groups.io
Sent: 02/09/2020 06:32:09
Subject: [jmri-developers] Min/max values for voltage/current meters for LcooNet, Z21, DCC++, Cbus?

Does anyone knows the minimum and maximum values of voltage and current meters for LocoNet, Z21, DCC++ and CBus?

If you know the resolution too, it would be great, but it's not that important.

DCC++ is measured in percent so I assume the min and max values are 0 and 100.0?

--------------------

The MultiMeter interface specified the unit for current, but not for voltage.

LocoNet is measured in amps. Is voltage measured in volts?

Z21 is measured in milliamps. Is voltage measured in millivolts?

Cbus is measured in milliamps. Is voltage measured in millivolts?

--------------------

Is it bad to add a meter icon to the PanelEditor without making it work on the web panel? I think I can get a meter icon work on the PanelEditor but it will be too much work for me to implement it for the web, partly because I'm not so used to work with web design. I could probably extend a text label or a memory icon to make the web work, but I might also add a graphical icon for displaying a meter that would need more work to work for the web panel.

I attach an image on one idea I have. The image shows two circular icons that shows an AnalogIO that may be a servo or a rotating crane or something like that. Something that rotates around its axle. It may be useful if you for example has a crane next to the track and want to see on the panel which position the crane has to the track. And below these two icons is a voltage/current meter.

Daniel




--
Andrew Crosland


Bob M.
 

The Digitrax LocoNet implementation of "Query Mode" is the basis of the
existing JMRI LocoNet MultiMeter implementation. jmrix.loconet.LnMultiMeter
interprets the messages:
- The reported DCC track Voltage is believed to be expressed as a 7 bit
integer representing 0.2V steps. This gives a range of 0.0V to 25.4V in
0.2V steps.
- The reported Input Current Draw is believed to be expressed as a 7 bit
integer representing 0.1A steps. This gives a range of 0.0A to 12.7A in
0.1A steps.

Whether this is an _accurate_ interpretation of the LocoNet messages is not
clear, as the LocoNet Monitor's underlying interpreter uses a different
interpretation.
Regards,
Bob M.


Ken Cameron
 

Were any of the volt/amp decoding for LocoNet from Digitrax documents or was
this from observation and reverse engineering the packets?

-Ken Cameron, Member JMRI Dev Team
www.jmri.org
www.fingerlakeslivesteamers.org
www.cnymod.org
www.syracusemodelrr.org


Bob M.
 

Ken C.,

My efforts on the LocoNet messages related to Query Mode voltage and current
reporting is from observation and reverse-engineering, plus the few "hints"
in Digitrax public info on Query Mode. Other developers may possiblly had
other info from Digitrax, though.

Regards,
Bob M.