GX developer: q-series... is there a problem with this thermocouple code?

Mas01

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A particular T/C module was only using ch2. I updated it to also use ch1 and ch3 (1st and 3rd channel). I don't even know what D114.1 means but I just guessed I needed a D114.0 and a D114.2, so I added the two legs into the code. Now, the thermocouples on ch1 and ch3 are showing good values when I inject a temperature, but D114.0 and D114.2 are shown in blue (I'm using monitor mode to show values of registers). Why are they blue but D114.1 is not blue?
For info g49 is for error detection on the thermocouple module. Thanks

IMG_20211021_194948.jpg
 
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D114.0 means the first bit of D114 16 bit register, D114.1 the second etc.

D114.0 and D114.2 are set because they are probably set to 1 elsewhere in the program
 
U14\G49.0 .... Etc. are buffer memory addresses read from the card, These must be status bits so they refer to the status of the analogue channels, off hand not sure what they are but most Q series analogue cards use buffer memory 49 as input signal detection error, so it seems that you either do not have the channels set up correctly or more likely the TC probes are not connected, so effectively these are alarms.
I cannot remember if the G49.xx bits show up in status modes so it is possible that these are used elsewhere, I would just change the D114.0 & 2 to say a couple of M Bits that are not used, if they still show blue (i.e. True) then there is a problem with the channels as above, also do a search for D114.0 & 2 also D114, it may be it is used elsewhere.

Also as a matter of fact your recent post on the TO instruction is the same as Uxx\G xx
So TO/FROM are send & read buffer memories as are the same as using the Uxx\G.. but able to set/read at bit level.
 
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U14\G49.0 .... Etc. are buffer memory addresses read from the card, These must be status bits so they refer to the status of the analogue channels, off hand not sure what they are but most Q series analogue cards use buffer memory 49 as input signal detection error, so it seems that you either do not have the channels set up correctly or more likely the TC probes are not connected, so effectively these are alarms.
I cannot remember if the G49.xx bits show up in status modes so it is possible that these are used elsewhere, I would just change the D114.0 & 2 to say a couple of M Bits that are not used, if they still show blue (i.e. True) then there is a problem with the channels as above, also do a search for D114.0 & 2 also D114, it may be it is used elsewhere.

Also as a matter of fact your recent post on the TO instruction is the same as Uxx\G xx
So TO/FROM are send & read buffer memories as are the same as using the Uxx\G.. but able to set/read at bit level.
I think you've hit the nail on the head.
In my haste to see a "valid" temperature reading, I twisted together the bare green & white wires of the TC cable...at the moment, there's no TC probes fitted to ch1 and ch3. I will inject a proper signal by fitting a 2-prong TC connector on the cable and injecting a temperature properly using a Fluke signal generator. Hopefully, the channels will be error free, if I do that.
Cheers again - I shall report back with the results. Thanks
 
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GXDeveloper is a bit of a pain, the Newer GXWorks2 is far better, you can configure the cards in a parameter like automatically assign registers for the analogue values & so on, there is very little need to do any ladder program to get the information from intelligent cards.
It would be best to find the manual on the analogue cards.

Here is the one I think you need

https://dl.mitsubishielectric.com/dl/fa/document/manual/plc/sh080141/sh080141p.pdf
 
Update...no error detection on ch1 or ch3 when properly connected to the signal generator.
I wish I had GX works2, but I'm stuck with GX developer at the moment.
Thanks again.
 

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