BX-xxUT Configuration in DMD

[johnr]

Hi guys,

Just finished my initial test of one of the new temperature modules, in this case the BX-04UT.  It's showing much better accuracy on J and K type thermocouples than what I was getting with the 04THM.  I thought I should bring one little thing to your attention in the Do-More software though.

When configuring the module in DMD I was (initially) disappointed to observe on the configuration dialog screen, that I would only get 1 Degree F or C resolution per count, instead of 0.1 degrees as is the case for the 04THM.  I didn't understand why a module with much higher A/D resolution would have less usable resolution, but I continued anyways...  Then I was pleased to find out when I actually started up the unit that my resolution was the same as before, 0.1 degrees per count.  No scaling changes necessary.  Yay!!

Please tell me that the unit is right and the DMD software is wrong.  I tend to believe that's the case, particularly when I noticed that RTD's and thermistors only show 1 degree per count as well - I would expect 0.1 or 0.01 for RTDs, maybe even a decimal further for thermistors.  Don't have a way to test them to find out what they're really showing.

[BobO]

The primary channel value is in RX, not WX. WX was included for compatibility with existing modules, but the 1/1024th of degree precision really needs to be rendered into a float.

[johnr]

Got it - thanks!  I didn't think to look beyond the WX registers

[BobO]

And yes, the WX description is incorrect. We first had the WX values as whole degrees for simplicity, and changed it to make it compatible with the x10 value in the other modules. We'll fix the UI.

[johnr]

After seeing your reply, I noticed that the RX register values were hiding in plain sight, right there on the channel configuration detail page.   

When I started the configuration change, I went first to the I/O mappings page to look at the overview of the address differences between my existing 04THM and the UT.  I didn't see the RX addresses there, so I didn't train my my mind look for them elsewhere.
 Perhaps they should be added to the I/O mappings as well, or is it a rule throughout the Do-More system that any WX/WY address assignments will have corresponding RX/RY values as well?  Thanks

[BobO]

After seeing your reply, I noticed that the RX register values were hiding in plain sight, right there on the channel configuration detail page.   

When I started the configuration change, I went first to the I/O mappings page to look at the overview of the address differences between my existing 04THM and the UT.  I didn't see the RX addresses there, so I didn't train my my mind look for them elsewhere.
 Perhaps they should be added to the I/O mappings as well, or is it a rule throughout the Do-More system that any WX/WY address assignments will have corresponding RX/RY values as well?  Thanks

The RX/RY scales are always associated with the WX/WY I/O. For temperature modules, we hacked it. We needed a place to publish the higher precision values, and it was either create a structure to do so, or use the associated scale. We chose the scale. Unfortunately that isn't as intuitive and we need to do better...just not sure what to do yet.