Emerson SI-PROFIBUS

Unidrive M SI-PROFIBUS User Guide 93
Issue Number: 3
Safety
information
Introduction
Mechanical
installation
Electrical
installation
Getting
started
Parameters
GSD
Files
Cyclic data
Non-cyclic
data
Control and
status words
Diagnostics
PROFIdrive
profile (V4)
Advanced
features
Legacy
features
Glossary of
terms
Index
Example response - success
Data word = 0x1663
Stamp number = 6
Data low byte = 0x63 = 99
If there was a problem with writing the data to the defined parameter, e.g. parameter is
read only, does not exist, or data is out of range, the ERR bit is set to 1.
Example response - success
Data word = 0x5663
Stamp number = 6
14.6.4 Abort CT Single Word non-cyclic message
The internal state machine that controls the non-cyclic data transfer will only accept a
new telegram if it contains the next expected telegram (i.e. after accepting Telegram 2,
the state machine will only respond to Telegram 3. If Telegram 4 is received, it will be
ignored).
If an error occurs in the master controller that causes the telegrams to get out of step,
the master controller program should time-out, abort the message and reset the non-
cyclic state machine.
A Mode 1 non-cyclic message can be abandoned by resetting the state machine. This is
done by setting the non-cyclic word to 0.
Example telegram
Data word = 0x0000
Stamp number = 0
14.6.5 16-bit parameter access
Normally six telegrams would be required to access drive parameters using Mode 1
non-cyclic data. When accessing 16-bit data only four telegrams are required. If an
attempt is made to read a 32-bit parameter from the drive the parameter value will be
returned, provided that the parameter value does not exceed signed 16-bit limits. If the
value is larger than a signed 16-bit value, the ERR bit will be set. When writing data to a
32-bit parameter, the 16-bit data will be treated as a signed 16-bit data value. This limits
the range that can be written to a 32-bit parameter.
Bit b15-b12 b11-b8 b7-b4 b3-b0
Value 0001 0110 0110 0011
Bit b15-b12 b11-b8 b7-b4 b3-b0
Value 0101 0110 0110 0011
Bit b15-b12 b11-b8 b7-b4 b3-b0
Value 0000 0000 0000 0000