modbus ASCII library

[gdah]

Does anyone have some example on modbus ASCII library??

thanks...

[gdah]

currently i'm using this program. but when i send 3A30 3330 3430 3030 3030 3030 3246 370D 0A to my device. nothing happen.my device not responding. what should i do??

[tst]

Are your settings correct?

Does this work with these settings in programs like Modbus Scanner?

[gdah]

hi tst,

yes,my setting is correct. i referred to the decive manual.mode=ASCII,flow control=none, parity=even, baud rate=19200. i using the same program for power relay device in different setting and it's working. but when i used the same setting as i mention before,it's not working. do u have any labview program that using modbus library??if u do, then mayb i can test it with my device..

thanks

[gdah]

hi tst,
yes,my setting is correct. i referred to the decive manual.mode=ASCII,flow control=none, parity=even, baud rate=19200. i using the same program for power relay device in different setting and it's working. but when i used the same setting as i mention before,it's not working. do u have any labview program that using modbus library??if u do, then mayb i can test it with my device..

thanks

[Wayne.C]

gdah,

Here are some more serial settings to double check for ASCII mode.

Start Bit = 1

Data Bits = 7

Parity = Odd, Even or None depending on the device you are communicating with.

Stop Bits = 1 if parity is set to Odd or Even, 2 if parity is set to None. 

[JB]

It seems that there is a bug in the original Modbus library when the number of coils/register is greater than 16. I have not tested it because this is not the case in my application.

Please see the comments and their links at the bottom of this page.

[tst]

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gdah wrote:

i using the same program for power relay device in different setting and it's working. but when i used the same setting as i mention before,it's not working.

---

Which would indicate that the code works. My guess would be that the manual is incomplete or that you're not performing a required step.

As I said, I suggest you try using a program like Modbus Scanner to connect to the device. If you can't do it there, you won't be able to do it in LabVIEW.

[gdah]

thanks everyone..

i'm appreciate your helps..maybe there are some missing information of my device that i not realize. i will come back to you if i have problems..

thanks...

[gdah]

hi everyone..

i have read all the information about the software. but my device stil not working.can anyone help me??i hav e download a modbus scanner from internet. i tested with my device but unfortunately it stil didn't work. I used mode=ASCII, parity=even, baud=19200,bit data=7, stop bit=1.I get wrong data when i want to read input registers value. if anyone have another modbus scanner that mayb will solve my problem? Right now  i stil do not know either my connection serial setting is correct or not.