issue reading Process Image byte variables

[livesource]

Hi,

I am having an issue reading any of the Process Image byte variables ... ie. DIn_Status, DOut_Status, RevPiLED all return 00000000 regardless of the actual state.

Example

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piTest -w DOutBit_1,1 

Success - Activates OUT 0 LED on the unit

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piTest -1 -q -r DOutBit_1

Success - Returns "1"

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piTest -1 -q -r DOut_Status,b

Fail - Returns "00000000"
I Expected - "10000000" from this. Have I got something wrong here? How can I read all the DOut_x bits in one piTest command?

I posted about this last week here viewtopic.php?f=6&t=2884#p10472, but still haven't got a response. I'm really hoping someone can help me here as I've got quite a tight deadline to get this project working. I've also just plugged in a ModBus slave and am having a similar issue with that... I can read BOOL variables ie Input_Bit_1 = 1 but not WORD variables ie Input_Word_1 = 00000000 00000000.


Thanks for any suggestions!

[livesource]

Additional issue: Modbus_Actions_Status errors not resetting

The example below is for an action configured as follows

Action #2 | 95 | READ_HOLDING_REGISTERS | 40004 |1 | 1000 | Input_Word_7


1.

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piTest -q -r Modbus_Action_Status_2

This returns "2"
I understand 2 = ILLEGAL DATA ADDRESS

2.
I now want to reset the error code on Modbus_Action_Status_2 so that I can try a different address and check if the error is reported again.
I remove Action 2 from the Extended Data GUI so that the error is not regenerated while poling, then...

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piTest -w Action_Status_Reset_2,1

This returns "Set bit 1 on byte at offset 207. Value 1"

3.

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piTest -q -r Modbus_Action_Status_2

This still returns "2"
I expected this would be 0

Modbus_Master_Status is 0 the whole time. The variable Input_Word_7 is also 0 the whole time. I am able to read the addresses 40004 the slave fine using a gui on my PC and it returns 5. I was also able to read 40004 using minimalmodbus on the revPi, but I had to use "Raw Address" "3" rather than 40004. I'm not sure if this Raw Addressing is common or something particular to the monnit gateway I am working with.

[nicolaiB]

Hi

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piTest -1 -q -r DOut_Status,b

Fail - Returns "00000000"
I Expected - "10000000" from this. Have I got something wrong here? How can I read all the DOut_x bits in one piTest command?

Why do you expect a different value than 0? Extract from the wiki:

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DOut_Status: if this byte has a value not equal to zero, the digital outputs were cutout due to emergency. Bit 5 indicates overheating (150 °C). As soon as the error state is over, DOut_Status goes back to zero. D

[nicolaiB]

Hi,

please remove any register configuration and restart the modbus driver / reset the action. Is it still != 0?

Regarding the raw address: I have a Modbus RTU meter connected to my RevPi and having the same issue that the register address is specified with 30007, but I have to use 7 in order to get data. Ihmo this comes from the original Modbus specs which where written with Modicon controllers in mind where the function code was encoded in the address.

Nicolai

[saardrimer]

I think that some of the issues I've been experiencing are related:

viewtopic.php?f=6&t=2905

Could there be something about Modbus registers with 5 digits being mishandled somehow?

It would be great to know what is causing this issue and if it's a piTest issue or something else.