Publication 1766-RM001A-EN-P - October 2008
Recipe and Data Logging 531
Controller Responds with Reply
If the data integrity check fails, the record is deleted and an error is sent
with STS of 0xF0 and ext STS of 0x0E.
For more information on writing a DF1 protocol, refer to Allen-Bradley
publication 1770-6.5.16
, DF1 Protocol and Command Set Reference
Manual (available from http://www.literature.rockwellautomation.com
).
Conditions that Will
Erase the Data Retrieval
File
The following conditions will cause previously logged data to be lost:
• Program download from RSLogix 500/RSLogix Micro to controller.
• Memory Module transfer to controller except for Memory Module
autoload of the same program.
• Full Queue - when a queue is full, new records are recorded over
the existing records, starting at the beginning of the file. You can put
the following rung in your ladder program to prevent this from
happening:
NOTE
The last byte will be a zero value representing the terminator character.
Reply Structure
SRC DST CMD 4f STS TNS DATA EXT STS
Table 5:
Field Function Description
SRC Source Node
DST Destination Node
CMD Command Code
STS Status Code
TNS Transaction Number Always 2 bytes
DATA Formatted string
IMPORTANT
The data in the retrieval file can only be read once. Then it is erased
from the processor.
efesotomasyon.com - Allen Bradley,Rockwell,plc,servo,drive
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