osa_tor5 Posted February 10, 2023 Report Share Posted February 10, 2023 Hello everyone, I got stucked with one issue during programming PLC. I am not fluen with MODBUS and I cannot resolve communication/data problem. I have GPS tracker MB-GPS-1 by F&F, it works with RTU MODBUS (datasheet attached). When BIT Liczenie is ON it should read values of time, date, Latitude, Longitude etc. Problem is, despite all comunication settings are the same, Tx Rx leds are blinking but data are still 0. I wonder if data type is ok but I cannot change it to INT/UINT8, it has to be at least 16. Also I can see Status = 3 and I am not sure what does it mean... Is anyone able to help me please? I work with factory settings - Slave ID 1 , parity none, baud rate 9600, bit stop 2. 74×105 FF MB-GPS-1 inst E220912 EN.PDF Quote Link to comment Share on other sites More sharing options...
pascal Posted February 13, 2023 Report Share Posted February 13, 2023 you are adressing adress 16..... reading the manual -> time is 0x10 -> adres 10 ????? Quote Link to comment Share on other sites More sharing options...
osa_tor5 Posted February 13, 2023 Author Report Share Posted February 13, 2023 I tried many addresses, the description doesn't matter for now. HEX 0x10 = DEC 16. The problem is that I always read "0" regardless of the address I use in the program..... And what does it mean "status = 3"? Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted February 13, 2023 MVP 2023 Report Share Posted February 13, 2023 You must use standard Modbus PC software and USB to RS485 converter for connect to GPS tracker. In this case you can find working combination of command and address. After you can implement this settings to PLC. Quote Link to comment Share on other sites More sharing options...
osa_tor5 Posted February 20, 2023 Author Report Share Posted February 20, 2023 Thank you for advice. Problem has been solved. Problem was with jumper terminating the receiver and without PC sofware it could take many days to discover the problem. Best regards Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.