Hello everyone, I’m after some advice with how Wonderware Intouch deals with strings and hopefully where I’m going wrong.
I’m trying to compare two strings in a Schneider Quantum 984 PLC. One entered via the SCADA and the other read from a RFID tag. The SCADA to PLC comms is Modbus TCP.
When the PLC reads the registers from the RFID tag any blanks in the sting are entered in the PLC as 0’s. When the same string is entered via the SCADA the blanks are entered as spaces (hex code 20).
For example:
The string is across 4 registers.
RFID I/O Message = 400001-400004 M
SCADA I/O Message = 400101-400104 M
RFID Read Tag
400001 = 3537 Hex (57 ASCII char)
400002 = 3333 Hex (33 ASCII char)
400003 = 0000 Hex ( ASCII char)
400004 = 0000 Hex ( ASCII char)
SCADA Entered Tag
400101 = 3537 Hex (57 ASCII char)
400102 = 3333 Hex (33 ASCII char)
400103 = 2020 Hex ([space,space] ASCII char)
400104 = 2020 Hex ([space,space] ASCII char)
When looking in the smc diagnostics the value coulomb shows the spaces added to the SCADA entry (R/H justified |).
RFID = 5733|
SCADA = 5733 |
Any idea how I stop the SCADA adding in the spaces?
Any advice would be greatly appreciated.
Thanks
I’m trying to compare two strings in a Schneider Quantum 984 PLC. One entered via the SCADA and the other read from a RFID tag. The SCADA to PLC comms is Modbus TCP.
When the PLC reads the registers from the RFID tag any blanks in the sting are entered in the PLC as 0’s. When the same string is entered via the SCADA the blanks are entered as spaces (hex code 20).
For example:
The string is across 4 registers.
RFID I/O Message = 400001-400004 M
SCADA I/O Message = 400101-400104 M
RFID Read Tag
400001 = 3537 Hex (57 ASCII char)
400002 = 3333 Hex (33 ASCII char)
400003 = 0000 Hex ( ASCII char)
400004 = 0000 Hex ( ASCII char)
SCADA Entered Tag
400101 = 3537 Hex (57 ASCII char)
400102 = 3333 Hex (33 ASCII char)
400103 = 2020 Hex ([space,space] ASCII char)
400104 = 2020 Hex ([space,space] ASCII char)
When looking in the smc diagnostics the value coulomb shows the spaces added to the SCADA entry (R/H justified |).
RFID = 5733|
SCADA = 5733 |
Any idea how I stop the SCADA adding in the spaces?
Any advice would be greatly appreciated.
Thanks
Last edited: