Author Topic: Write in input 1 in Nano 10  (Read 1620 times)

acxysty

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Write in input 1 in Nano 10
« on: December 16, 2011, 01:37:30 AM »
Hi

We are not sure that we have well understood the mapping adress syntax with Nano 10

Here is our problem :

We want to write a 1 in input#1 using Modbus TCPIP protocol.

For that we intent to use MB function 05 (Force I/O bit). Then we need to specify the adress : 0x9C41 (for 40001 Is that right ?) and the value OxFF00.

How can we be sure that bit 1 only of Input [1] will modify ? How about to modify input#2 ?

Thank you in advance for your help/support

Thierry

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Re:Write in input 1 in Nano 10
« Reply #1 on: December 16, 2011, 08:33:02 AM »
Please refer to the last column of Table 14.1 in the Nano-10 User's Manual which maps the inputs bit address to Modbus function 05 address.

So
input #1 = address 0
input #2 = address 1

You can use these addresses to turn on/off an input or an output using Modbus function 05.

When you try to change a physical input it will only change for 1 scan time and on the next I/O scan the input will be changed back to whatever the physical input senses.

So the only way to know if an input has been triggered is to latch the input to a relay or output or to run a custom function and display something on the LCD screen.
Email: support@triplc.com
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acxysty

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Re:Write in input 1 in Nano 10
« Reply #2 on: December 16, 2011, 08:42:50 AM »
Thank you for your quick answer that make us to understand !


One more question :

I/O are refresh everyscan with physical value. What about the I/O not related to a physical I/O ? Do they remain in the same state ?

regards

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Re:Write in input 1 in Nano 10
« Reply #3 on: December 16, 2011, 09:24:56 AM »
During I/O scan:

1) Physical input states are checked and updated to the internal variable INPUT[n]

2) computed value of variables OUTPUT[n] are updated to the physical outputs.

All internal variables such as RELAY[n], TIMER[n] A to Z etc are not affected by the I/O scan.
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acxysty

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Re:Write in input 1 in Nano 10
« Reply #4 on: December 19, 2011, 07:33:40 AM »
According to some tests we have observed that only input#1 to imput#8 are refreshed during scaning, all other input#N (N>9) being unchanged.

Will you confirm that please ?

Thnak you in advance.

Thierry

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Re:Write in input 1 in Nano 10
« Reply #5 on: December 19, 2011, 09:55:36 AM »
Since Nano-10 only has 4 physical inputs and is not expandable, so only a single byte representing the first 8 inputs are used and updated by the I/O scan cycle.

On bigger and expandable PLC such as FMD and F-series, the first 128 physical inputs are scanned and updated by default,  regardless of whether you have expanded to the maximum inputs or not.


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acxysty

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Re:Write in input 1 in Nano 10
« Reply #6 on: December 19, 2011, 10:03:35 AM »
Just great ! Thank you