Leroy-Somer digitax st User Manual page 41

TELEGRAM 6
The sixth telegram from the PROFIBUS-DP master has the stamp number set to 6. The
data bits contain the low data byte for the parameter that is being written to.
Example telegram
Bit
Value
Data word = 0x1663
Stamp number = 6
Data low byte = 0x63 = 99
When the sixth telegram has been received and processed in the slave node, it will write
the data (Pr 1.21 = 12553.9) as transmitted (the decimal point is automatically inserted
when the data is transferred to the drive). If the operation is successful, the ERR bit is
reset to 0 and the telegram is reflected in the non-cyclic IN word.
Example response - success
Bit
Value
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
Bit
Value
Data word = 0x5663
Stamp number = 6
8.7.4 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
Bit
Value
Data word = 0x0000
Stamp number = 0
SM-PROFIBUS DP-V1 User Guide
Issue : a
b15-b12 b11-b8
0001 0110
b15-b12 b11-b8
0001 0110
b15-b12 b11-b8
0101 0110
b15-b12 b11-b8
0000 0000
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b7-b4 b3-b0
0110 0011
b7-b4 b3-b0
0110 0011
b7-b4 b3-b0
0110 0011
b7-b4 b3-b0
0000 0000
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