Data Types; Send Request / Enquiry Telegram - BONFIGLIOLI Vectron Agile Communications Manual

Protocol
7.2.2

Data Types

The number of data bytes depends on the type of the corresponding parameter. A maximum of 99
data bytes can be transferred.
Data Type
uInt
Int
Long
String
Parameter values with decimal places are transferred without the decimal point. Depending on the
number of decimal places, the values are multiplied by 10, 100 or 1000.
The number of decimal places for the corresponding parameters is set in the frequency inverter. In
this way it is made sure that the sent parameter values are processed with the correct number of
decimal places.
Example: Frequency value with data type Long:
Value to be transferred = 100.25 Hz. The numerical value transmitted in the telegram is 10025, which
corresponds to 0x2729 in HEX format. Since the data type is Long, 8 bytes are transferred
("wwwwwwww").
00002729
Example: Current value with data type Int:
The value to be transmitted is 10.3 A. The numerical value transmitted in the telegram is 103, which
corresponds to 0x67 in HEX format. Since the data type is Int, 4 bytes are transferred ("wwww").
0067
7.2.3

Send Request / Enquiry Telegram

Via the enquiry telegram of the bus master, the frequency inverter is requested to send the data con-
tent of the relevant parameter. In the enquiry response telegram, the frequency inverter sends the
requested data to the bus master. The master completes the transmission with EOT.
Bus Master
EOT ADR
Frequency Inverter
ADR STX SYS ds n
or in the case of an error:
ADR NAK
Bus Master
EOT
If no response from the frequency inverter is received within an adjustable response time (see chap-
ter 7.4, "Monitoring Function (Timing / Watchdog)"), or if the frequency inverter returns incorrect
data, the enquiry telegram is repeated three times (maximum of three transmissions possible).
NAK signals an error. An error may have different causes. Errors may be caused by transmission fail-
ures, incorrect data or an incorrect string.
06/2010
Type No. of Data Bytes "w"
unsigned Integer
Integer
Long
char. string
Frequency Inverter
SYS ds n
Bus Master
n n a a
Frequency Inverter
Data Types Used
04
04
08
variable, up to 99
n n ENQ
w w w ... ... w
VABus Agile
Value Range No. of Bits
0 ... 65535
-32768 ... +37767
31 31
-2 ... +2 -1
-
w w ETX BCC
16
16
32
variable
27