Reference Manual User Manual

Publication 1747-RM623D-EN-P - June 2006
A-2 Local Database Access Using PLC-5 MSG Instructions
• Data-table address in destination processor - The destination
file must be N7, otherwise the request will be rejected.
• PLC-5 Typed Read and PLC-5 Typed Write: N7:XX
where XX is the zero-based element offset in the Local
Database file
• PLC-2 Unprotected Read, PLC-2 Unprotected Write: YY
where YY is the octal zero-based element offset in the Local
Database file
• Port number - set to 2 for the ControlNet network
• Flags:
• .TO - forces a message to timeout
• .EW - indicates that the message is waiting for an open
connection
• .CO - indicates that the message is sent
• .ER - indicates that the message was terminated due to an
error
• .DN - indicates that the message was sent without error
• .ST - indicates that the message was started
• .EN - indicates that the message instruction is enabled
• Error code – indicates the error when the .ER is set
For each concurrently enabled MSG instruction, the PLC-5 processor
opens an unscheduled connection.
All messages sent over different connections to the 1747-SCNR
scanner have the same priority.