Skip to Content

Register Login

Industry Online Support

Technical Forum

Navigation

problem with cp341 (1CH02) modbus master.I dont know where should I exactly enter the slave address number!

Created by: CHILICHILIBOMBOM at: 2/2/2011 10:51 AM (12 Replies)

Rating (0)

Thanks 0

Result pages:: |; 1 | 2; |

13 Entries

Entries per page: 10 | all

2/2/2011 10:51 AM	Rate (0)
CHILICHILIBOMBOM Posts: 20 Rating: (0)	Hello experts I have a confusing problem with cp341 (1CH02) modbus master.I dont know where should I exactly enter the slave address nomber!!!I dont have any problem with other entrances such as Len or start address. I would be appreciate if you consider my post soon. Splitted from cp341-modbus master.
CHILICHILIBOMBOM Posts: 20 Rating: (0)	Last edited by: O_Moderator at: 2/2/2011 11:38 AM new subject after splitting
Suggestion To thank Quote Answer

2/2/2011 2:36 PM	Rate (0)
Kaulquappe Posts: 3093 Rating: (323)	Hello Chilichilibombom, you have to insert the slave address in the first byte of the send DB. Just have a look at the Modbus master manual, section 6. Regards, Kaulquappe
Kaulquappe Posts: 3093 Rating: (323)
Suggestion To thank Quote Answer

2/3/2011 4:07 PM	Rate (0)
CHILICHILIBOMBOM Posts: 20 Rating: (0)	I already read the manual but I mixed up!please take a look at the sample example of simens related to Modbus,I mean zXXX21_01_PtP_Com_CP34x. where should I put the slave nomber?At the first Byte of DB40,DB41,DB42 or DB43? Thanks in advance.
CHILICHILIBOMBOM Posts: 20 Rating: (0)
Suggestion To thank Quote Answer

2/3/2011 4:16 PM	Rate (0)
CHILICHILIBOMBOM Posts: 20 Rating: (0)	In this sample example would you explain more. I know that DB21 & DB22 used for FB7 & FB8.But what about other DBs?what are them?which one is Send DB?
CHILICHILIBOMBOM Posts: 20 Rating: (0)
Suggestion To thank Quote Answer

2/3/2011 4:36 PM	Rate (0)
dchartier Grandmaster-Expert Joined: 9/27/2006 Last visit: 1/4/2025 Posts: 12321 Rating: (2697)	Hello Chillichilllbombom; Have a look at the attached extract from the sample program oif the Modbus driver manual. In this example they have set DB 42 a the Send DB. This is not shown in the example, so you can build your own DNB based on the Function Code you want to call in your program. Follow the structure sown in the function codes chapter; whatever Function Code you call, the slave address will be in the 1rst byte of the SendDB you create. Hope this helps, Daniel Chartier. Attachment Modbus SendDB.JPG (216 Downloads)

Suggestion To thank Quote Answer

2/3/2011 10:50 PM	Rate (0)
CHILICHILIBOMBOM Posts: 20 Rating: (0)	Would you complete my attached DB42 for example if I want to read some registers with function code 4 whereas the slave number is 5 and 12 registers should be read. Thanks a lot dear dchartier. Attachment untitled.jpg (171 Downloads)
CHILICHILIBOMBOM Posts: 20 Rating: (0)
Suggestion To thank Quote Answer

2/4/2011 1:07 PM	Rate (0)
Kaulquappe Posts: 3093 Rating: (323)	Hello Chilichilibombom, you should use the Modbus Master example zXX21_04_PtP_Com_MODMA. Regards, Kaulquappe
Kaulquappe Posts: 3093 Rating: (323)
Suggestion To thank Quote Answer

2/4/2011 9:00 PM	Rate (0)
CHILICHILIBOMBOM Posts: 20 Rating: (0)	Thanks dear expert for attention.But this sample in not added to my sample examples of siematic manager 5.4 what should I do now? How can I add MODMA to my sample examples?
CHILICHILIBOMBOM Posts: 20 Rating: (0)
Suggestion To thank Quote Answer

2/4/2011 9:50 PM	Rate (0)
Kaulquappe Posts: 3093 Rating: (323)	Hello Chilichilibombom, when you install the Modbus master package the example is installed too. http://support.automation.siemens.com/WW/view/en/27774018 Regards, Kaulquappe
Kaulquappe Posts: 3093 Rating: (323)
Suggestion To thank Quote Answer

2/5/2011 5:07 AM	Rate (0)
Asanga Regular Member Joined: 2/5/2009 Last visit: 10/20/2024 Posts: 11 Rating: (0)	Hello Chilichilibombom, Pls. follow the attached PLC prog. which I have programmed my customer point. FC 2, DB 142 & DB 143 will help for you. Regards, Asanga. Attachment My_proj.zip (198 Downloads)

Suggestion To thank Quote Answer

|

Share this page:

Share this page on...

Follow us on