ProSoft Technology MVI56-AFC - Manual (Page 175)

MVI56-AFC ♦ ControlLogix Platform MVI56-AFC Backplane Communication
Liquid and Gas Flow Computer User Manual
ProSoft Technology, Inc. Page 175 of 316
February 25, 2011
Special Notes
Monitoring Bit 0 (R) of the Block ID Element of the Input Function Block
This bit is set to 1 if a Pass-Through Modbus message from a SCADA host
was present.
This bit is set to 0 if no message was present.
Monitoring Bit 1 (B) of the Block ID Element of the Input Function Block
This bit is set to 1 if the Modbus message from a SCADA host was a bit write
- Modbus function code 5 or 15.
This bit is set to 0 if the Modbus message from a SCADA host was a word
write - Modbus function codes 1 or 16.
Monitoring Bit 2 (W) of the Block ID Element of the Input Function Block
This bit is set to 1 if the Modbus message from the SCADA host was longer
than the data block size you defined - Overflow Status.
This bit is set to 0 if the Modbus message from a SCADA host was
successfully transferred to the controller (or flushed).
Note: Refer to Function Block Structure (page 168) for information on Bit 8 and 9 settings.
Function 4 is the same as function 6, except that the received command remains
pending even if no overflow occurred; this allows you to "pre-inspect" the
command before completing its processing with function 6. Functions 5 and 7 are
the same as functions 4 and 6 respectively, except that for word-write commands
(Modbus function codes 6 and 16) pairs of words in the data are swapped.
11.2.5 Function Block Definition - 8: Meter Process Variables
Output Function Block ID